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Kuété MA, Van Velthem P, Ballout W, Klavzer N, Nysten B, Ndikontar MK, Pardoen T, Bailly C. Eco-Friendly Blends of Recycled PET Copolymers with PLLA and Their Composites with Chopped Flax Fibres. Polymers (Basel) 2023; 15:3004. [PMID: 37514394 PMCID: PMC10384891 DOI: 10.3390/polym15143004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/04/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
The structure and properties of blends of a novel polyethylene terephthalate copolymer (COPET) obtained by chemical recycling of commercial PET with high-molar-mass poly-L-lactide (PLLA) are investigated and compared to corresponding composites with chopped flax fibres. The focus is on the morphology at nano- and micro-scales, on the thermal characteristics and on the mechanical behaviour. The blends are immiscible, as evidenced by virtually unchanged glass transition temperatures of the blend components compared to the neat polymers (49 °C for COPET and 63 °C for PLLA by DSC). At low PLLA content, the blends display a sea-island morphology with sub-micron to micron droplet sizes. As the composition approaches 50/50, the morphology transitions to a coarser co-continuous elongated structure. The blends and composites show strongly improved stiffness compared to COPET above its glass transition temperature, e.g., from melt behaviour at 60 °C for COPET alone to almost 600 MPa for the 50/50 blend and 500 MPa for the 20% flax composite of the 80/20 COPET/PLLA blend. The flax fibres increase the crystallisation rate of PLLA in blends with dispersed PLLA morphology. The evidence of cavitation on the fracture surfaces of blends shows that despite the immiscibility of the components, the interfacial adhesion between the phases is excellent. This is attributed to the presence of aliphatic ester spacers in COPET. The tensile strength of the 80/20 blend is around 50 MPa with a Young's modulus of 2250 MPa. The corresponding 20% flax composite has similar tensile strength but a high Young's modulus equal to 6400 MPa, which results from the individual dispersion and strong adhesion of the flax fibres and leads close to the maximum possible reinforcement of the composite, as demonstrated by tensile tests and nano-indentation. The Ashby approach to eco-selection relying on the embodied energy (EE) further clarifies the eco-friendliness of the blends and their composites, which are even better positioned than PLLA in a stiffness versus EE chart.
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Affiliation(s)
- Martial Aimé Kuété
- Institute of Condensed Matter and Nanosciences-Bio & Soft Matter (IMCN/BSMA), UCLouvain, 1348 Louvain-la-Neuve, Belgium
- Institute of Mechanics, Materials and Civil Engineering, UCLouvain, 1348 Louvain-la-Neuve, Belgium
- Macromolecular Chemistry Unit, Applied Chemistry Laboratory, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 812, Cameroon
| | - Pascal Van Velthem
- Institute of Condensed Matter and Nanosciences-Bio & Soft Matter (IMCN/BSMA), UCLouvain, 1348 Louvain-la-Neuve, Belgium
| | - Wael Ballout
- Institute of Condensed Matter and Nanosciences-Bio & Soft Matter (IMCN/BSMA), UCLouvain, 1348 Louvain-la-Neuve, Belgium
| | - Nathan Klavzer
- Institute of Mechanics, Materials and Civil Engineering, UCLouvain, 1348 Louvain-la-Neuve, Belgium
| | - Bernard Nysten
- Institute of Condensed Matter and Nanosciences-Bio & Soft Matter (IMCN/BSMA), UCLouvain, 1348 Louvain-la-Neuve, Belgium
| | - Maurice Kor Ndikontar
- Macromolecular Chemistry Unit, Applied Chemistry Laboratory, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 812, Cameroon
| | - Thomas Pardoen
- Institute of Mechanics, Materials and Civil Engineering, UCLouvain, 1348 Louvain-la-Neuve, Belgium
| | - Christian Bailly
- Institute of Condensed Matter and Nanosciences-Bio & Soft Matter (IMCN/BSMA), UCLouvain, 1348 Louvain-la-Neuve, Belgium
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2
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Laws TS, Mei H, Terlier T, Verduzco R, Stein GE. Tailoring the Wettability and Substrate Adherence of Thin Polymer Films with Surface-Segregating Bottlebrush Copolymer Additives. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:7201-7211. [PMID: 37172215 DOI: 10.1021/acs.langmuir.3c00703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We developed "reactive" bottlebrush polymers based on styrene (S) and t-butyl acrylate (tBA) as additives for polystyrene (PS) coatings. The bottlebrush polymers spontaneously bloom to both the air and substrate interfaces during solution casting. While neat PS films are hydrophobic and poorly adhere to the native oxide on clean silicon wafers, the hydrophilicity and substrate adherence of bottlebrush-incorporating PS films can be tailored through the thermally activated deprotection of tBA to produce acrylic acid (AA) and acrylic anhydride (AH). A critical design parameter is the manner by which tBA is incorporated into the bottlebrush: When the bottlebrush side chains are copolymers of S and tBA, the extent of deprotection is extremely low, even after prolonged thermal annealing at elevated temperature. However, when the bottlebrush contains a mixture of poly(t-butyl acrylate) (PtBA) and PS side chains, nearly all tBA is converted to AA and AH. Consequently, using the "mixed-chain" bottlebrush design with thermal processing and appropriate conditioning, the water contact angle is reduced from over 90° on unmodified PS down to 75° on bottlebrush-incorporating PS films, and the substrate adherence is improved in proportion to the extent of tBA deprotection.
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Affiliation(s)
- Travis S Laws
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Hao Mei
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
| | - Tanguy Terlier
- SIMS Laboratory, Shared Equipment Authority, Rice University, Houston, Texas 77005, United States
| | - Rafael Verduzco
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
- Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - Gila E Stein
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
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3
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Bae S, Noack MM, Yager KG. Surface enrichment dictates block copolymer orientation. NANOSCALE 2023; 15:6901-6912. [PMID: 36876525 DOI: 10.1039/d3nr00095h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Orientation of block copolymer (BCP) morphology in thin films is critical to applications as nanostructured coatings. Despite being well-studied, the ability to control BCP orientation across all possible block constituents remains challenging. Here, we deploy coarse-grained molecular dynamics simulations to study diblock copolymer ordering in thin films, focusing on chain makeup, substrate surface energy, and surface tension disparity between the two constituent blocks. We explore the multi-dimensional parameter space of ordering using a machine-learning approach, where an autonomous loop using a Gaussian process (GP) control algorithm iteratively selects high-value simulations to compute. The GP kernel was engineered to capture known symmetries. The trained GP model serves as both a complete map of system response, and a robust means of extracting material knowledge. We demonstrate that the vertical orientation of BCP phases depends on several counter-balancing energetic contributions, including entropic and enthalpic material enrichment at interfaces, distortion of morphological objects through the film depth, and of course interfacial energies. BCP lamellae are found more resistant to these effects, and thus more robustly form vertical orientations across a broad range of conditions; while BCP cylinders are found to be highly sensitive to surface tension disparity.
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Affiliation(s)
- Suwon Bae
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA.
| | - Marcus M Noack
- The Center for Advanced Mathematics for Energy Research Applications, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Kevin G Yager
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA.
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4
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Giunta G, Smith L, Bartha K, Karimi-Varzaneh HA, Carbone P. Understanding the balance between additives' miscibility and plasticisation effect in polymer composites: a computational study. SOFT MATTER 2023; 19:2377-2384. [PMID: 36920461 DOI: 10.1039/d2sm01642g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Plasticisers are small organic molecules routinely added to polymer composites that modify the processability of the compounds by adsorbing on the filler's surface or dispersing into the polymer matrix. Here using a simple yet chemically specific coarse-grained model, we demonstrate that the filler surface coverage and the degree of dispersion into the polymer matrix can be tuned without modifying the chemistry of the plasticisers but only by varying their conformational flexibility. We show that when the adsorption mechanism and clustering into the bulk are entropically driven as in this work, this is a general phenomenon independent on the polymer chemistry and its molecular weight. Our findings suggest a simple practical design rule that requires only minor modifications of the plasticisers' chemistry to achieve maximum adsorption onto the filler surface or dispersion into the polymer matrix.
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Affiliation(s)
- Giuliana Giunta
- Department of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13 9PL, Manchester, UK.
| | - Lois Smith
- Department of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13 9PL, Manchester, UK.
| | - Kristof Bartha
- Department of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13 9PL, Manchester, UK.
| | | | - Paola Carbone
- Department of Chemical Engineering, School of Engineering, The University of Manchester, Oxford Road, M13 9PL, Manchester, UK.
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5
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Chen YJ, Yu HY. Enthalpic Interactions and Solution Behaviors of Solvent-Free Polymer Brushes. Polymers (Basel) 2022; 14:polym14235237. [PMID: 36501627 PMCID: PMC9740690 DOI: 10.3390/polym14235237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 12/04/2022] Open
Abstract
We performed molecular dynamics simulations to characterize the role of enthalpic interaction in impacting the static and dynamic properties of solvent-free polymer brushes. The intrinsic enthalpic interaction in the simulation was introduced using different attraction strengths between distinct species. Two model systems were considered: one consisting of binary brushes of two different polymer types and the other containing a mixture of homopolymer brushes and free molecules. In the first system, we observed that, when two originally incompatible polymers were grafted to opposing surfaces, the miscibility between them was significantly enhanced. A less favorable intrinsic enthalpic interaction in the brushes resulted in a more stretched chain configuration, a lower degree of inter-brush penetration, and faster segmental relaxation. In the second system, we characterized the solvent capacity of the homopolymer brushes from variations in the energy components of the system as a function of the number of free molecules. We determined that molecular absorption was driven by the release of the entropic frustration for the grafted chains in conjunction with the chemical affinity between the solutes and polymers. The solute distribution function within the inter-wall space showed that solute-polymer mixing in the middle of the gap occurred preferentially when the enthalpic interaction was more favorable. When this was not the case, absorption was predominantly localized near the grafting surface. From the mean square displacement of the solute, we found that the brush profiles restrained the molecular diffusion perpendicular to the grafting wall; the weaker the attraction from the brush, the higher the solute mobility.
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Understanding microstructural heterogeneity in low and high molecular weight fractions of polydisperse polyisobutylene by SEC and NMR for its reactivity. JOURNAL OF POLYMER RESEARCH 2022. [DOI: 10.1007/s10965-022-03289-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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7
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Lee D, Charpota N, Mei H, Terlier T, Pietrzak D, Stein GE, Verduzco R. Impact of Processing Effects on Surface Segregation of Bottlebrush Polymer Additives. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dongjoo Lee
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
| | - Nilesh Charpota
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Hao Mei
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
| | - Tanguy Terlier
- SIMS Lab, Shared Equipment Authority, Rice University, Houston, Texas 77005, United States
| | - Danica Pietrzak
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
| | - Gila E. Stein
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Rafael Verduzco
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
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8
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Lei Z, Zhang Z, Xu L, Yao J, Chen F, Liu Y. GUS Aerogel Modified Phenolic Nanocomposites: Effects of Inhomogeneous Cross-Linking Characteristics and Interfacial Phase Properties on the Mechanical Behavior. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zixuan Lei
- Department of Chemical Engineering, School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
| | - Zhongzhou Zhang
- Department of Chemical Engineering, School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
| | - Li Xu
- Department of Chemical Engineering, School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
| | - Jiayu Yao
- Department of Chemical Engineering, School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
| | - Fei Chen
- Department of Chemical Engineering, School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
| | - Yuhong Liu
- Department of Chemical Engineering, School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
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9
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Moonprasith N, Date J, Sako T, Kida T, Hiraoka T, Yamaguchi M. Segregation Behavior of Miscible PC/PMMA Blends during Injection Molding. MATERIALS 2022; 15:ma15092994. [PMID: 35591328 PMCID: PMC9105524 DOI: 10.3390/ma15092994] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/19/2022] [Accepted: 04/19/2022] [Indexed: 02/01/2023]
Abstract
Miscible blends composed of bisphenol-A polycarbonate (PC) and poly(methyl methacrylate) (PMMA), in which one of them has low molecular weight, were employed to study the surface segregation behavior during flow. The blend samples showed typical rheological behaviors, such as simple polymer melts without a long-time relaxation mechanism ascribed to phase separation, demonstrating that they were miscible. After injection molding, the amounts of a low molecular weight component on the blend surface were found to be larger than the actual blend ratio. Because the injection-molded products were transparent despite a huge difference in refractive indices between PC and PMMA, they showed no phase separation. This result demonstrated that surface segregation of a low molecular weight component occurred under flow field, which expands the material design such as tough plastics with good scratch resistance and optical fibers with tapered refractive index.
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Affiliation(s)
- Nantina Moonprasith
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Japan; (N.M.); (J.D.); (T.S.); (T.K.)
- Sirindhorn International Institute of Technology, Thammasat University, 99 Moo 18, Paholyothin, Khlong Luang 12120, Thailand
| | - Jitsuhiro Date
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Japan; (N.M.); (J.D.); (T.S.); (T.K.)
| | - Takumi Sako
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Japan; (N.M.); (J.D.); (T.S.); (T.K.)
| | - Takumitsu Kida
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Japan; (N.M.); (J.D.); (T.S.); (T.K.)
| | - Tatsuhiro Hiraoka
- Hiroshima R&D Center, Mitsubishi Chemical Corporation, 20-1, Miyukicho, Otake, Hiroshima 739-0693, Japan;
| | - Masayuki Yamaguchi
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Japan; (N.M.); (J.D.); (T.S.); (T.K.)
- Correspondence: ; Tel.: +81-761-51-1621
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10
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Ahmadi‐Dehnoei A, Ghasemirad S. Tuning adhesion performance of an acrylic pressure‐sensitive adhesive using polysilsesquioxane‐acrylic core‐shell nanoparticles. J Appl Polym Sci 2022. [DOI: 10.1002/app.52429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Ali Ahmadi‐Dehnoei
- Polymer Engineering Department, Faculty of Chemical Engineering Tarbiat Modares University Tehran Iran
| | - Somayeh Ghasemirad
- Polymer Engineering Department, Faculty of Chemical Engineering Tarbiat Modares University Tehran Iran
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11
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Opdam J, Govers SPW, Melio J, van der Ven LGJ, de With G, Tuinier R, Esteves ACC. Distribution of block copolymers in drying polymer films. J Colloid Interface Sci 2022; 612:617-627. [PMID: 35016021 DOI: 10.1016/j.jcis.2021.12.130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/18/2021] [Accepted: 12/20/2021] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS Block copolymers (BCP) consisting of a polar block and a surface active apolar block are widely used for surface functionalization of polymer films. The characteristics of the copolymer blocks determine whether surface segregation and/or phase separation occurs, for a given bulk mixture. This data can be used to find the optimal BCP composition where high surface enrichment is obtained without accumulation of phase separated BCP in the bulk. METHODS The distribution of poly(ethylene oxide)-polydimethylsiloxane (PEO-PDMS) BCP in a polymer formulation relevant for coating applications is systematically investigated. The surface segregation is studied in liquid formulations with surface tension measurements and dried films with X-ray photoelectron spectroscopy (XPS), whereas phase separation is quantified using turbidity measurements. The results are compared with Scheutjens-Fleer self-consistent field (SF-SCF) computations, which are also applied to determine the effect of film drying on BCP phase stability and surface segregation. FINDINGS Longer PDMS blocks result in lower interfacial tension of the liquid polymer mixture, whereas for the cured films, the largest PDMS concentration at the interface was obtained for intermediate PDMS block lengths. This is explained by the observation that phase separation already occurs at very low BCP concentrations for long PDMS blocks. The SCF predictions qualitatively agree with the experimental results and reveal that the BCP distribution changes significantly during film drying.
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Affiliation(s)
- Joeri Opdam
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands
| | - Stefan P W Govers
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands
| | - Julio Melio
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands; Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, the Netherlands
| | - Leendert G J van der Ven
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands
| | - Gijsbertus de With
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands
| | - Remco Tuinier
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands.
| | - A Catarina C Esteves
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, the Netherlands.
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12
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Schulz M, Brinkhuis R, Crean C, Sear RP, Keddie JL. Suppression of self-stratification in colloidal mixtures with high Péclet numbers. SOFT MATTER 2022; 18:2512-2516. [PMID: 35297936 DOI: 10.1039/d2sm00194b] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The non-equilibrium assembly of bimodal colloids during evaporative processes is an attractive means to achieve gradient or stratified layers in thick films. Here, we show that the stratification of small colloids on top of large is prevented when the viscosity of the continuous aqueous phase is too high. We propose a model where a too narrow width of the gradient in concentration of small colloids suppresses the stratification.
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Affiliation(s)
- M Schulz
- Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK.
| | - R Brinkhuis
- Allnex, Nieuwe Kanaal 7N, 6709 PA Wageningen, The Netherlands
| | - C Crean
- Department of Chemistry, University of Surrey, Guildford, Surrey, GU2 7XH, UK
| | - R P Sear
- Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK.
| | - J L Keddie
- Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK.
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13
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Eickelmann S, Moon S, Liu Y, Bitterer B, Ronneberger S, Bierbaum D, Breitling F, Loeffler FF. Assessing Polymer-Surface Adhesion with a Polymer Collection. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:2220-2226. [PMID: 35138112 PMCID: PMC8867722 DOI: 10.1021/acs.langmuir.1c02724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 01/26/2022] [Indexed: 06/14/2023]
Abstract
Polymer modification plays an important role in the construction of devices, but the lack of fundamental understanding on polymer-surface adhesion limits the development of miniaturized devices. In this work, a thermoplastic polymer collection was established using the combinatorial laser-induced forward transfer technique as a research platform, to assess the adhesion of polymers to substrates of different wettability. Furthermore, it also revealed the influence of adhesion on dewetting phenomena during the laser transfer and relaxation process, resulting in polymer spots of various morphologies. This gives a general insight into polymer-surface adhesion and connects it with the generation of defined polymer microstructures, which can be a valuable reference for the rational use of polymers.
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Affiliation(s)
- Stephan Eickelmann
- Max-Planck-Institute
of Colloids and Interfaces, Biomolecular Systems, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Sanghwa Moon
- Max-Planck-Institute
of Colloids and Interfaces, Biomolecular Systems, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Yuxin Liu
- Max-Planck-Institute
of Colloids and Interfaces, Biomolecular Systems, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Benjamin Bitterer
- Institute
of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Sebastian Ronneberger
- Max-Planck-Institute
of Colloids and Interfaces, Biomolecular Systems, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Dominik Bierbaum
- Max-Planck-Institute
of Colloids and Interfaces, Biomolecular Systems, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Frank Breitling
- Institute
of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Felix F. Loeffler
- Max-Planck-Institute
of Colloids and Interfaces, Biomolecular Systems, Am Muehlenberg 1, 14476 Potsdam, Germany
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14
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Kim KH, Nam J, Choi J, Seo M, Bang J. From macromonomers to bottlebrush copolymers with sequence control: synthesis, properties, and applications. Polym Chem 2022. [DOI: 10.1039/d2py00126h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bottlebrush polymers (BBPs) are a type of comb-like macromolecules with densely grafted polymeric sidechains attached to the polymer backbones, and many intriguing properties and applications have been demonstrated due to...
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15
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Foster JC, DeVol TA, Husson SM. Membranes for the Capture and Screening of Waterborne Plutonium Based on a Novel Pu-Extractive Copolymer Additive. MEMBRANES 2021; 12:3. [PMID: 35054528 PMCID: PMC8779412 DOI: 10.3390/membranes12010003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/13/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
This contribution describes the fabrication of plutonium-adsorptive membranes by non-solvent induced phase separation. The dope solution comprised poly(vinylidene fluoride) (PVDF) and a Pu-extractive copolymer additive of PVDF-g-poly(ethylene glycol methacrylate phosphate) (EGMP) in dimethylformamide (DMF). The effects of casting conditions on membrane permeability were determined for PVDF membranes prepared with 10 wt% PVDF-g-EGMP. Direct-flow filtration and alpha spectrometry showed that membranes containing the graft copolymer could recover Pu up to 59.9 ± 3.0% from deionized water and 19.3 ± 3.5% from synthetic seawater after filtering 10 mL of 0.5 Bq/mL 238Pu. SEM-EDS analysis indicated that the graft copolymer was distributed evenly throughout the entire depth of the copolymer membranes, likely attributing to the tailing observed in the alpha spectra for 238Pu. Despite the reduction in resolution, the membranes exhibited high Pu uptake at the conditions tested, and new membrane designs that promote copolymer surface migration are expected to improve alpha spectrometry peak energy resolutions. Findings from this study also can be used to guide the development of extractive membranes for chromatographic separation of actinides from contaminated groundwater sources.
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Affiliation(s)
- James C. Foster
- Department of Chemical and Biomolecular Engineering, Clemson University, 127 Earle Hall, Clemson, SC 29634, USA;
- Nuclear Environmental Engineering Sciences, Radioactive Waste Management Center, Clemson University, Clemson, SC 29625, USA;
| | - Timothy A. DeVol
- Nuclear Environmental Engineering Sciences, Radioactive Waste Management Center, Clemson University, Clemson, SC 29625, USA;
- Department of Environmental Engineering and Earth Sciences, Clemson University, 342 Computer Court, Anderson, SC 29625, USA
| | - Scott M. Husson
- Department of Chemical and Biomolecular Engineering, Clemson University, 127 Earle Hall, Clemson, SC 29634, USA;
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16
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Toth K, Bae S, Osuji CO, Yager KG, Doerk GS. Film Thickness and Composition Effects in Symmetric Ternary Block Copolymer/Homopolymer Blend Films: Domain Spacing and Orientation. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01032] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kristof Toth
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520, United States
| | - Suwon Bae
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Chinedum O. Osuji
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Kevin G. Yager
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Gregory S. Doerk
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States
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17
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Zhang Y, Liu Z, Zhang X, Guo S. Sandwich-Layered Dielectric Film with Intrinsically Excellent Adhesion, Low Dielectric Constant, and Ultralow Dielectric Loss for a High-Frequency Flexible Printed Circuit. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c01676] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Yang Zhang
- The State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, China
| | - Zhiyu Liu
- The State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, China
| | - Xianlong Zhang
- The State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, China
| | - Shaoyun Guo
- The State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, China
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18
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Lee C, Osuji CO. 100th Anniversary of Macromolecular Science Viewpoint: Opportunities for Liquid Crystal Polymers in Nanopatterning and Beyond. ACS Macro Lett 2021; 10:945-957. [PMID: 35549196 DOI: 10.1021/acsmacrolett.1c00350] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Liquid-crystal polymers (LCPs) integrate at a molecular level the characteristics of two important material classes, i.e., liquid crystals (LCs) and polymers. As a result, they exhibit a wide variety of intriguing physical phenomena and have useful properties in various settings. In the nearly 50 years since the discovery of the first melt-processable LCPs, there has been a remarkable expansion in the field encompassing the development of new chain architectures, the incorporation of new classes of mesogens, and the exploration of new properties and applications. As engineering materials, LCPs are historically best known in the context of high strength fibers. In a more contemporary study, the pairing of LC mesophase assembly with block copolymer (BCP) self-assembly in LC BCPs has resulted in a fascinating interplay of ordering phenomena and rich phase behavior, while lightly cross-linked networks, LC elastomers, are extensively investigated as shape memory materials based on their thermomechanical actuation. As this Viewpoint describes, these and other examples are active areas of research in which new, compelling opportunities for LCPs are emerging. We highlight a few selected areas that we view as being potentially significant in the near future, with a particular emphasis on nanopatterning. Here, the ability to readily access small feature sizes, the fluidity of the LC mesophase, and LC-based handles for achieving orientation control present a compelling combination. Opportunities for LCPs are also presented under the broad rubric of "beyond nanopatterning", and we discuss relevant challenges and potential new directions in the field.
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Affiliation(s)
- Changyeon Lee
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Chinedum O. Osuji
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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19
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Łojkowski M, Chlanda A, Choińska E, Swieszkowski W. Water vapor induced self-assembly of islands/honeycomb structure by secondary phase separation in polystyrene solution with bimodal molecular weight distribution. Sci Rep 2021; 11:13299. [PMID: 34168207 PMCID: PMC8225630 DOI: 10.1038/s41598-021-92594-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 06/02/2021] [Indexed: 11/11/2022] Open
Abstract
The formation of complex structures in thin films is of interest in many fields. Segregation of polymer chains of different molecular weights is a well-known process. However, here, polystyrene with bimodal molecular weight distribution, but no additional chemical modification was used. It was proven that at certain conditions, the phase separation occurred between two fractions of bimodal polystyrene/methyl ethyl ketone solution. The films were prepared by spin-coating, and the segregation between polystyrene phases was investigated by force spectroscopy. Next, water vapour induced secondary phase separation was investigated. The introduction of moist airflow induced the self-assembly of the lower molecular weight into islands and the heavier fraction into a honeycomb. As a result, an easy, fast, and effective method of obtaining island/honeycomb morphologies was demonstrated. The possible mechanisms of the formation of such structures were discussed.
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Affiliation(s)
- Maciej Łojkowski
- Faculty of Material Sciences and Engineering, Warsaw University of Technology, Wołoska 141, 02-507, Warsaw, Poland.
- Centre for Advanced Materials and Technology CEZAMAT, Warsaw University of Technology, Warsaw, Poland.
| | - Adrian Chlanda
- Faculty of Material Sciences and Engineering, Warsaw University of Technology, Wołoska 141, 02-507, Warsaw, Poland
- Department of Chemical Synthesis and Flake Graphene, Łukasiewicz Research Network - Institute of Microelectronics and Photonics, Aleja Lotników 32/46, 02-668, Warsaw, Poland
| | - Emilia Choińska
- Faculty of Material Sciences and Engineering, Warsaw University of Technology, Wołoska 141, 02-507, Warsaw, Poland
| | - Wojciech Swieszkowski
- Faculty of Material Sciences and Engineering, Warsaw University of Technology, Wołoska 141, 02-507, Warsaw, Poland.
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20
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Peñas MI, Ocando C, Penott-Chang E, Safari M, Ezquerra TA, Rebollar E, Nogales A, Hernández R, Müller AJ. Nanostructural organization of thin films prepared by sequential dip-coating deposition of poly(butylene succinate), poly(ε-caprolactone) and their copolyesters (PBS-ran-PCL). POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123812] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Marks MA, Kalaitzidou K, Gutekunst WR. Synthesis and Characterization of Cationic Dendrimer-PDMS Hybrids. Macromol Rapid Commun 2021; 42:e2000652. [PMID: 33368765 PMCID: PMC8085078 DOI: 10.1002/marc.202000652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/01/2020] [Indexed: 12/19/2022]
Abstract
A modular strategy for the synthesis of dendron-linear polymer hybrids comprised of a flexible polydimethylsiloxane (PDMS) midblock with cationic 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) dendron end groups is developed. The invention of a scalable methodology to access quaternary ammonium carboxylate building blocks and their direct use in esterification chemistry enables rapid access to cationic bis-MPA dendrons. The convergent click coupling of highly charged dendrons to hydrophobic PDMS chain-ends gives a 12-membered family of hybrids that are comprised of different dendron generations (G1-3) and quaternary ammonium alkyl chain lengths (C4 , C8 , C12 , C16 ). This provides a library of materials with variable hydrophobicity, charge density, and chain-end valency. The physical behavior of the dendron-linear PDMS hybrid copolymers significantly changes after introduction of the cationic dendron end-groups and leads to soft-solid materials as a result of inhibited chain mobility. These PDMS-dendron hybrids are expected to behave as surface-active antimicrobial additives in bulk cross-linked silicone systems.
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Affiliation(s)
- Monica A Marks
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Kyriaki Kalaitzidou
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Will R Gutekunst
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
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22
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Kim KH, Kim M, Moon J, Huh J, Bang J. Bottlebrush Copolymer as Surface Neutralizer for Vertical Alignment of Block Copolymer Nanodomains in Thin Films. ACS Macro Lett 2021; 10:346-353. [PMID: 35549064 DOI: 10.1021/acsmacrolett.0c00879] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Herein we designed bottlebrush copolymers for use as a neutral additive to block copolymer (BCP) thin films in which they are segregated to the interfaces via architectural effects and produce nonpreferential interfaces to induce perpendicular orientation of BCP microdomains. Two BCP systems were employed, a conventional poly(styrene-b-methyl methacrylate) (PS-b-PMMA) with relatively low χ and similar surface energies between blocks, and a high χ poly(styrene-b-methacrylic acid) (PS-b-PMAA) with distinct surface energies. The bottlebrushes, with either short side-chains of PS-r-PMMA or PS-r-PMAA random copolymers, were synthesized via ring-opening metathesis polymerization (ROMP). Remarkably, it was observed that the top and bottom interfaces of both BCP films were enriched with bottlebrush copolymers, regardless of the surface energy difference between blocks, hence, vertically oriented microdomains were achieved for both BCP systems. This can be attributed to the screening of polymer interactions by a good solvent during the spin-casting process, allowing architectural effects to play a role in surface segregation of bottlebrush copolymers, as confirmed by contact angle measurements and time-of-flight secondary ion mass spectroscopy (TOF-SIMS). We believe that this concept can be further extended to various applications that require polymer films with functional surfaces.
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Affiliation(s)
- Ki Hyun Kim
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Mincheol Kim
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Junsoo Moon
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - June Huh
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Joona Bang
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
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23
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Yamamoto S, Tanaka K. Entropy-driven segregation in epoxy-amine systems at a copper interface. SOFT MATTER 2021; 17:1359-1367. [PMID: 33325969 DOI: 10.1039/d0sm01600d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The composition of an epoxy resin at the interface with the adherend is usually different from that in the bulk due to the enrichment of a specific constituent, a characteristic called interfacial segregation. For better adhesion, it should be precisely understood how epoxy and amine molecules exist on the adherend surface and react with each other to form a three-dimensional network. In this study, the entropic factor of the segregation in a mixture of epoxy and amine at the copper interface before and after the curing reaction is discussed on the basis of a full-atomistic molecular dynamics (MD) simulation. Smaller molecules were preferentially segregated at the interface regardless of the epoxy and amine, and this segregation remained after the curing process. No segregation occurred at the interface for a combination composed of epoxy and amine molecules with a similar size. These findings make it clear that the size disparity between constituents affects the interfacial segregation via the packing and/or translational entropy. The curing reaction was slower near the interface than in the bulk, and a large amount of unreacted molecules remained there. Finally, the effect of molecular shape was also examined. Linear molecules were more likely to segregate than round-shaped ones even though they were similar in volume. We believe that these findings, which are difficult to obtain experimentally, contribute to the understanding of the interfacial adhesion phenomena on a molecular scale.
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Affiliation(s)
- Satoru Yamamoto
- Centre for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan.
| | - Keiji Tanaka
- Centre for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan. and Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395, Japan. and Department of Automotive Science, Kyushu University, Fukuoka 819-0395, Japan and International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, Fukuoka 819-0395, Japan
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24
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Antonioli D, Chiarcos R, Gianotti V, Terragno M, Laus M, Munaò G, Milano G, De Nicola A, Perego M. Inside the brush: partition by molecular weight in grafting to reactions from melt. Polym Chem 2021. [DOI: 10.1039/d1py01303c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A substantial partition by molecular weight takes place during the grafting to reactions.
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Affiliation(s)
- Diego Antonioli
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Riccardo Chiarcos
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, 15121 Alessandria, Italy
- CNR-IMM, Unit of Agrate Brianza, Via C. Olivetti 2, 20864 Agrate Brianza, Italy
| | - Valentina Gianotti
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Margherita Terragno
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Michele Laus
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Gianmarco Munaò
- Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università degli Studi di Messina, Viale F. Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Giuseppe Milano
- Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Naples 80125, Italy
| | - Antonio De Nicola
- Dipartimento di Chimica e Biologia “A. Zambelli”, Universitá degli Studi di Salerno, via G. Paolo II 134, 84084, Fisciano, SA, Italy
| | - Michele Perego
- CNR-IMM, Unit of Agrate Brianza, Via C. Olivetti 2, 20864 Agrate Brianza, Italy
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25
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Laus M, Chiarcos R, Gianotti V, Antonioli D, Sparnacci K, Munaò G, Milano G, De Nicola A, Perego M. Evidence of Mechanochemical Control in “Grafting to” Reactions of Hydroxy-Terminated Statistical Copolymers. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c02142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Michele Laus
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, Alessandria 15121, Italy
| | - Riccardo Chiarcos
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, Alessandria 15121, Italy
| | - Valentina Gianotti
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, Alessandria 15121, Italy
| | - Diego Antonioli
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, Alessandria 15121, Italy
| | - Katia Sparnacci
- Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Universitá del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, Alessandria 15121, Italy
| | - Gianmarco Munaò
- Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università degli Studi di Messina, Viale F. Stagno d’Alcontres 31, Messina 98166, Italy
| | - Giuseppe Milano
- Department of Organic Materials Science, Yamagata University, 4-3-16 Jonan Yonezawa, Yamagata-ken 992-8510, Japan
| | - Antonio De Nicola
- Department of Organic Materials Science, Yamagata University, 4-3-16 Jonan Yonezawa, Yamagata-ken 992-8510, Japan
| | - Michele Perego
- CNR-IMM, Unit of Agrate Brianza, Agrate Brianza 20864, Italy
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26
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Šindelka K, Lísal M. Interplay between surfactant self-assembly and adsorption at hydrophobic surfaces: insights from dissipative particle dynamics. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1857863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Karel Šindelka
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences, Institute of Chemical Process Fundamentals, Prague, Czech Republic
| | - Martin Lísal
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences, Institute of Chemical Process Fundamentals, Prague, Czech Republic
- Department of Physics, Faculty of Science, Jan Evangelista Purkyně University in Ústí nad Labem, Ústí nad Labem, Czech Republic
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27
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Competitive Adsorption of Ionic Liquids Versus Friction Modifier and Anti-Wear Additive at Solid/Lubricant Interface—Speciation with Vibrational Sum Frequency Generation Spectroscopy. LUBRICANTS 2020. [DOI: 10.3390/lubricants8110098] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A modern lubricant contains various additives with different functionalities and the interactions or reactions between these additives could induce synergistic or antagonistic effects in tribological performance. In this study, sum frequency generation (SFG) spectroscopy was used to investigate competitive adsorption of lubricant additives at a solid/base oil interface. A silica substrate was used as a model solid surface. The lubricant additives studied here included two oil-soluble ionic liquids (ILs, [N888H][DEHP] and [P8888][DEHP]), an antiwear additive (secondary ZDDP), an organic friction modifier (OFM), and a dispersant (PIBSI). Our results showed that for mixtures of ZDDP and IL in a base oil (PAO4), the silica surface is dominated by the IL molecules. In the cases of base oils containing OFM and IL, the silica/lubricant interface is dominated by OFM over [N888H][DEHP], while it is preferentially occupied by [P8888][DEHP] over OFM. The presence of PIBSI in the mixture of PAO4 and IL leads to the formation of a mixed surface layer at the silica surface with PIBSI as a major component. The SFG results in this investigation provide fundamental insights that are helpful to design the formulation of new lubricant additives of desired properties.
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28
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Schulz M, Smith RW, Sear RP, Brinkhuis R, Keddie JL. Diffusiophoresis-Driven Stratification of Polymers in Colloidal Films. ACS Macro Lett 2020; 9:1286-1291. [PMID: 35638630 DOI: 10.1021/acsmacrolett.0c00363] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The molecular composition of polymer blend surfaces defines properties such as adhesion, wetting, gloss, and biocompatibility. The surface composition often differs from the bulk because of thermodynamic effects or modification. Mixtures of colloids and linear polymers in a common solvent are often used to deposit films for use in encapsulants, inks, coatings, and adhesives. However, means to control the nonequilibrium surface composition are lacking for these systems. Here we show how the surface composition and hydrophilicity of a film deposited from a bimodal mixture of linear polymers and colloids in water can be adjusted simply by varying the evaporation rate. Ion beam analysis was used to quantify the extent of stratification of the linear polymers near the surface, and the results are in agreement with a recent diffusiophoretic model. Because our approach to stratification relies solely on diffusiophoresis, it is widely applicable to any system deposited from colloids and nonadsorbing polymers in solution as a means to tailor surface properties.
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Affiliation(s)
- Malin Schulz
- Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Richard W Smith
- Surrey Ion Beam Centre, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Richard P Sear
- Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | | | - Joseph L Keddie
- Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
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29
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Macromolecular Dyes by Chromophore-Initiated Ring Opening Polymerization of L-Lactide. Polymers (Basel) 2020; 12:polym12091979. [PMID: 32878177 PMCID: PMC7564406 DOI: 10.3390/polym12091979] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/27/2020] [Accepted: 08/28/2020] [Indexed: 11/16/2022] Open
Abstract
End functionalized polylactides are prepared by ring opening polymerization of L-lactide in the presence of stannous octoate (Sn(Oct)2). Three chromophores, 9H-carbazol-ethanol (CA), 9-fluorenyl-methanol (FM), and 2-(4-(2-chloro-4-nitrophenylazo)-N-ethylphenylamino)ethanol (Disperse Red 13, DR), are for the first time used as co-initiators in the polymerization process. The polymerization reaction is initiated by conventional thermal treatment, but in the case of FM, microwave-assisted polymerization is also carried out. CA and FM absorb and emit in the UV portion of the electromagnetic spectrum, whereas DR absorbs in the visible part. The obtained end-capped polylactides derivatives show the same photophysical properties as the initiator, so they are “macromolecular dyes” (MDs) that can be used “as synthesized” or can be blended with commercial poly(lactic acid) (PLA). The blends of PLA with MDs have ultraviolet-visible (UV-Vis) absorption and fluorescence emission features similar to that of MDs and thermal properties typical of PLA. Finally, migration tests, carried out onto the blends of PLA with MDs and PLA with free chromophores, show that MDs are less released than free chromophores both in solution and in the solid phase.
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30
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Miyagi K, Mei H, Terlier T, Stein GE, Verduzco R. Analysis of Surface Segregation of Bottlebrush Polymer Additives in Thin Film Blends with Attractive Intermolecular Interactions. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00744] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Kazuma Miyagi
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
| | - Hao Mei
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
| | - Tanguy Terlier
- SIMS Lab, Shared Equipment Authority, Rice University, Houston, Texas 77005, United States
| | - Gila E. Stein
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Rafael Verduzco
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
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31
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Kostrov SA, Gorodov VV, Sokolov BO, Muzafarov AM, Kramarenko EY. Low-Modulus Elastomeric Matrices for Magnetoactive Composites with a High Magnetic Field Response. POLYMER SCIENCE SERIES A 2020. [DOI: 10.1134/s0965545x20040082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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32
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Coote JP, Kinsey T, Street DP, Kilbey SM, Sangoro JR, Stein GE. Surface-Induced Ordering Depresses Through-Film Ionic Conductivity in Lamellar Block Copolymer Electrolytes. ACS Macro Lett 2020; 9:565-570. [PMID: 35648487 DOI: 10.1021/acsmacrolett.0c00039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Lamellar block copolymers based on polymeric ionic liquids (PILs) show promise as electrolytes in electrochemical devices. However, these systems often display structural anisotropy that depresses the through-film ionic conductivity. This work hypothesizes that structural anisotropy is a consequence of surface-induced ordering, where preferential adsorption of one block at the electrode drives a short-range stacking of the lamellae. This point was examined with lamellar diblock copolymers of polystyrene (PS) and poly(1-(2-acryloyloxyethyl)-3-butylimidazolium bis(trifluoromethanesulfonyl)imide) (PIL). The bulk PS-PIL structure was comprised of randomly oriented lamellar grains. However, in thin PS-PIL films (100-400 nm), the lamellae were stacked normal to the plane of the film, and islands/holes were observed when the as-prepared film thickness was incommensurate with the natural lamellar periodicity. Both of these attributes are well-known consequences of preferential wetting at surfaces. The ionic conductivity of thick PS-PIL films (50-100 μm) was approximately 20× higher in the in-plane direction than in the through-plane direction, consistent with a mixed structure comprised of randomly oriented lamellae throughout the interior of the film and highly oriented lamellae at the electrode surface. Therefore, to fully optimize the performance of a block copolymer electrolyte, it is important to consider the effects of surface interactions on the ordering of domains.
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33
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Tasche J, Sabattié EFD, Thompson RL, Campana M, Wilson MR. Oligomer/Polymer Blend Phase Diagram and Surface Concentration Profiles for Squalane/Polybutadiene: Experimental Measurements and Predictions from SAFT-γ Mie and Molecular Dynamics Simulations. Macromolecules 2020; 53:2299-2309. [PMID: 32308214 PMCID: PMC7161083 DOI: 10.1021/acs.macromol.9b02155] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 02/12/2020] [Indexed: 01/16/2023]
Abstract
The compatibility and surface behavior of squalane-polybutadiene mixtures are studied by experimental cloud point and neutron reflectivity measurements, statistical associating fluid theory (SAFT), and molecular dynamics (MD) simulations. A SAFT-γ Mie model is shown to be successful in capturing the cloud point curves of squalane-polybutadiene and squalane-cis-polybutadiene binary mixtures, and the same SAFT-γ Mie model is used to develop a thermodynamically consistent top-down coarse-grained force field to describe squalane-polybutadiene. Coarse-grained molecular dynamics simulations are performed to study surface behavior for different concentrations of squalane, with the system exhibiting surface enrichment and a wetting transition. Simulated surface profiles are compared with those obtained by fitting to neutron reflectivity data obtained from thin films composed of deuterated squalane (d-sq)-polybutadiene. The presented top-down parametrization methodology is a fast and thermodynamically reliable approach for predicting properties of oligomer-polymer mixtures, which can be challenging for either theory or MD simulations alone.
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Affiliation(s)
- Jos Tasche
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham DH1 3LE, United Kingdom
| | - Elise F D Sabattié
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham DH1 3LE, United Kingdom
| | - Richard L Thompson
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham DH1 3LE, United Kingdom
| | - Mario Campana
- Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX, United Kingdom
| | - Mark R Wilson
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham DH1 3LE, United Kingdom
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Mukherjee S, Xie R, Reynolds VG, Uchiyama T, Levi AE, Valois E, Wang H, Chabinyc ML, Bates CM. Universal Approach to Photo-Crosslink Bottlebrush Polymers. Macromolecules 2020. [DOI: 10.1021/acs.macromol.9b02210] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Sanjoy Mukherjee
- Materials Research Laboratory, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Mitsubishi Center for Advanced Materials, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Renxuan Xie
- Materials Research Laboratory, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Mitsubishi Center for Advanced Materials, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Veronica G. Reynolds
- Materials Department, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Mitsubishi Center for Advanced Materials, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Takumi Uchiyama
- Department of Materials Science and Engineering, Tokyo Institute of Technology, Tokyo 152-8552, Japan
| | - Adam E. Levi
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Mitsubishi Center for Advanced Materials, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Eric Valois
- Biomolecular Science and Engineering Graduate Program, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Hengbin Wang
- Mitsubishi Center for Advanced Materials, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Michael L. Chabinyc
- Materials Department, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Mitsubishi Center for Advanced Materials, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Christopher M. Bates
- Materials Department, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
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35
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Wessels MG, Jayaraman A. Self-assembly of amphiphilic polymers of varying architectures near attractive surfaces. SOFT MATTER 2020; 16:623-633. [PMID: 31808757 DOI: 10.1039/c9sm02104c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We use coarse-grained molecular dynamics simulations to investigate the assembly of A-B amphiphilic polymers near/on surfaces as a function of polymer architecture and surface attraction to the solvophobic B-block in the polymer. We study four polymer architectures: linear, bottlebrush with a backbone that is longer than each of the side chains, bottlebrush where the solvophobic backbone is similar in length to each of the side chains, and 'star-like' architectures where the backbone is significantly shorter than the side chain lengths. For each architecture and surface-B attraction, we quantify the assembled aggregate structure (i.e., aggregation number, domain shapes and sizes) and the chain conformations (i.e., components of the chain radius of gyration) on and away from the surface. For all the architectures and surface-B attraction strengths, the assembled structure away from the surface is similar to the assembly observed in bulk systems without surfaces. Near/on the surface, the assembled B-blocks form domains whose shapes and sizes are dependent on the surface-B attraction strength and the ability of the B-block in the polymer architecture to change conformations and pack on the surface. Domain sizes formed from linear and 'star-like' polymer architectures show the highest sensitivity to surface-B-block attraction strength, transitioning from hemispherical to disordered domains with increasing attraction strength. In contrast, bottlebrushes with long backbones and short side chains transition from hemispherical to striped to continuous domains with increasing surface-B attraction strength. Bottlebrushes with similar solvophobic backbone and side chain lengths form hemispherical domains that do not change significantly with the surface-B-block attraction strength. These computational results can guide experimentalists in their choices of surface chemistry and polymer architecture to achieve desired assembled domain shapes and sizes on the surface.
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Affiliation(s)
- Michiel G Wessels
- Colburn Laboratory, Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy Street, Newark, DE 19716, USA.
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36
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Wang HS, Oh S, Choi J, Jang W, Kim KH, Arellano CL, Huh J, Bang J, Im SG. High-Fidelity, Sub-5 nm Patterns from High-χ Block Copolymer Films with Vapor-Deposited Ultrathin, Cross-Linked Surface-Modification Layers. Macromol Rapid Commun 2020; 41:e1900514. [PMID: 31958190 DOI: 10.1002/marc.201900514] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 12/09/2019] [Indexed: 12/11/2022]
Abstract
Despite their capability, sub-10 nm periodic nano-patterns formed by strongly segregating block copolymer (BCP) thin films cannot be easily oriented perpendicular to the substrate due to the huge surface energy differences of the constituent blocks. To produce perpendicular nano-patterns, the interfacial energies of both the substrate and free interfaces should be controlled precisely to induce non-preferential wetting. Unfortunately, high-performance surface modification layers are challenging to design, and different kinds of surface modification methods must be devised respectively for each neutral layer and top coat. Furthermore, conventional approaches, largely based on spin-coating processes, are highly prone to defect formation and may readily cause dewetting at sub-10 nm thickness. To date, these obstacles have hampered the development of high-fidelity, sub-5 nm BCP patterns. Herein, an all-vapor phase deposition approach initiated chemical vapor deposition is demonstrated to form 9-nm-thick, uniform neutral bottom layer and top coat with exquisite control of composition and thickness. These layers are employed in BCP films to produce perpendicular cylinders with a diameter of ≈4 nm that propagate throughout a BCP thickness of up to ≈60 nm, corresponding to five natural domain spacings of the BCP. Such a robust approach will serve as an advancement for the reliable generation of sub-10 nm nano-patterns.
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Affiliation(s)
- Hyun Suk Wang
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Seula Oh
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Junhwan Choi
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Wontae Jang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Ki Hyun Kim
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Carlos Luis Arellano
- Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - June Huh
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Joona Bang
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Sung Gap Im
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
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37
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Zhang F, Yang L, Hu C, Li L, Wang J, Luo R, Wang Y. Phosphorylcholine- and cation-bearing copolymer coating with superior antibiofilm and antithrombotic properties for blood-contacting devices. J Mater Chem B 2020; 8:8433-8443. [DOI: 10.1039/d0tb01662d] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The phosphorylcholine- and cation-bering copolymer coating endowed the blood-contacting devices with superior antibiofilm and antithrombotic ability.
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Affiliation(s)
- Fanjun Zhang
- National Engineering Research Center for Biomaterials
- Sichuan University
- Chengdu 610064
- China
| | - Li Yang
- National Engineering Research Center for Biomaterials
- Sichuan University
- Chengdu 610064
- China
| | - Cheng Hu
- National Engineering Research Center for Biomaterials
- Sichuan University
- Chengdu 610064
- China
| | - Linhua Li
- National Engineering Research Center for Biomaterials
- Sichuan University
- Chengdu 610064
- China
| | - Jingyu Wang
- First Affiliated Hospital of Xi’an Jiaotong University
- Xi’an 710061
- China
| | - Rifang Luo
- National Engineering Research Center for Biomaterials
- Sichuan University
- Chengdu 610064
- China
| | - Yunbing Wang
- National Engineering Research Center for Biomaterials
- Sichuan University
- Chengdu 610064
- China
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38
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Mei H, Laws TS, Mahalik JP, Li J, Mah AH, Terlier T, Bonnesen P, Uhrig D, Kumar R, Stein GE, Verduzco R. Entropy and Enthalpy Mediated Segregation of Bottlebrush Copolymers to Interfaces. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01801] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
| | | | - Jyoti P. Mahalik
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | | | - Adeline H. Mah
- Materials Science and Engineering Program, University of Houston, Houston, Texas 77204, United States
| | | | - Peter Bonnesen
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - David Uhrig
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Rajeev Kumar
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
- Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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