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Lykins WR, Bernards DA, Schlesinger EB, Wisniewski K, Desai TA. Tuning polycaprolactone degradation for long acting implantables. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Li S, Lv D, Ai N, Shen J, Tonelli AE. A New Two‐Step Strategy for Encapsulating Amorphous Polymer Chains in Thiourea Crystals. MACROMOL CHEM PHYS 2020. [DOI: 10.1002/macp.202000269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Shanshan Li
- College of Chemical Engineering Zhejiang University of Technology Hangzhou Zhejiang 310014 China
- Zhejiang Province Key Laboratory of Biomass Fuel Zhejiang University of Technology Hangzhou Zhejiang 310014 China
- Fiber and Polymer Science Program, North Carolina State University Campus Box 8301, 1020 Main Campus Drive Raleigh NC 27606 USA
| | - Dongxu Lv
- College of Chemical Engineering Zhejiang University of Technology Hangzhou Zhejiang 310014 China
- Zhejiang Province Key Laboratory of Biomass Fuel Zhejiang University of Technology Hangzhou Zhejiang 310014 China
| | - Ning Ai
- Zhejiang Province Key Laboratory of Biomass Fuel Zhejiang University of Technology Hangzhou Zhejiang 310014 China
- College of Biological Chemical Science and Engineering Jiaxing University Jiaxing Zhejiang 314001 China
| | - Jialong Shen
- Fiber and Polymer Science Program, North Carolina State University Campus Box 8301, 1020 Main Campus Drive Raleigh NC 27606 USA
| | - Alan E. Tonelli
- Fiber and Polymer Science Program, North Carolina State University Campus Box 8301, 1020 Main Campus Drive Raleigh NC 27606 USA
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The 3D-Printed Bilayer's Bioactive-Biomaterials Scaffold for Full-Thickness Articular Cartilage Defects Treatment. MATERIALS 2020; 13:ma13153417. [PMID: 32756370 PMCID: PMC7436011 DOI: 10.3390/ma13153417] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/28/2020] [Accepted: 07/30/2020] [Indexed: 11/22/2022]
Abstract
The full-thickness articular cartilage defect (FTAC) is an abnormally severe grade of articular cartilage (AC) injury. An osteochondral autograft transfer (OAT) is the recommended treatment, but the increasing morbidity rate from osteochondral plug harvesting is a limitation. Thus, the 3D-printed bilayer’s bioactive-biomaterials scaffold is of major interest. Polylactic acid (PLA) and polycaprolactone (PCL) were blended with hydroxyapatite (HA) for the 3D-printed bone layer of the bilayer’s bioactive-biomaterials scaffold (B-BBBS). Meanwhile, the blended PLA/PCL filament was 3D printed and combined with a chitosan (CS)/silk firoin (SF) using a lyophilization technique to fabricate the AC layer of the bilayer’s bioactive-biomaterials scaffold (AC-BBBS). Material characterization and mechanical and biological tests were performed. The fabrication process consists of combining the 3D-printed structure (AC-BBBS and B-BBBS) and a lyophilized porous AC-BBBS. The morphology and printing abilities were investigated, and biological tests were performed. Finite element analysis (FEA) was performed to predict the maximum load that the bilayer’s bioactive-biomaterials scaffold (BBBS) could carry. The presence of HA and CS/SF in the PLA/PCL structure increased cell proliferation. The FEA predicted the load carrying capacity to be up to 663.2 N. All tests indicated that it is possible for BBBS to be used in tissue engineering for AC and bone regeneration in FTAC treatment.
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Tonelli AE. Enhancing the melt crystallization of polymers, especially slow crystallizing polymers like PLLA and PET. POLYMER CRYSTALLIZATION 2020. [DOI: 10.1002/pcr2.10095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Alan E. Tonelli
- Fiber & Polymer Science ProgramNorth Carolina State University, Wilson College of Textiles Raleigh North Carolina
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Ye HM, Chen XT, Li HF, Zhang P, Ma W, Li B, Xu J. Industrializable and sustainable approach for preparing extended-chain crystals of biodegradable poly(butylene succinate) and their applications. POLYMER 2019. [DOI: 10.1016/j.polymer.2018.11.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Prominently Promoting the Formation of Poly(butylene adipate) α-Form Crystals by Coalescing from Inclusion Complex. CHINESE JOURNAL OF POLYMER SCIENCE 2018. [DOI: 10.1007/s10118-018-2095-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Li S, Shen J, Tonelli AE. The influence of a contaminant in commercial PMMA: A purification method for its removal and its consequences. POLYMER 2018. [DOI: 10.1016/j.polymer.2017.12.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Gurarslan A, Joijode A, Shen J, Narayanan G, Antony GJ, Li S, Caydamli Y, Tonelli AE. Reorganizing Polymer Chains with Cyclodextrins. Polymers (Basel) 2017; 9:E673. [PMID: 30965971 PMCID: PMC6418566 DOI: 10.3390/polym9120673] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 11/14/2017] [Accepted: 11/22/2017] [Indexed: 11/17/2022] Open
Abstract
During the past several years, we have been utilizing cyclodextrins (CDs) to nanostructure polymers into bulk samples whose chain organizations, properties, and behaviors are quite distinct from neat bulk samples obtained from their solutions and melts. We first form non-covalently bonded inclusion complexes (ICs) between CD hosts and guest polymers, where the guest chains are highly extended and separately occupy the narrow channels (~0.5⁻1.0 nm in diameter) formed by the columnar arrangement of CDs in the IC crystals. Careful removal of the host crystalline CD lattice from the polymer-CD-IC crystals leads to coalescence of the guest polymer chains into bulk samples, which we have repeatedly observed to behave distinctly from those produced from their solutions or melts. While amorphous polymers coalesced from their CD-ICs evidence significantly higher glass-transition temperatures, Tgs, polymers that crystallize generally show higher melting and crystallization temperatures (Tms, Tcs), and some-times different crystalline polymorphs, when they are coalesced from their CD-ICs. Formation of CD-ICs containing two or more guest homopolymers or with block copolymers can result in coalesced samples which exhibit intimate mixing between their common homopolymer chains or between the blocks of the copolymer. On a more practically relevant level, the distinct organizations and behaviors observed for polymer samples coalesced from their CD-ICs are found to be stable to extended annealing at temperatures above their Tgs and Tms. We believe this is a consequence of the structural organization of the crystalline polymer-CD-ICs, where the guest polymer chains included in host-IC crystals are separated and confined to occupy the narrow channels formed by the host CDs during IC crystallization. Substantial degrees of the extended and un-entangled natures of the IC-included chains are apparently retained upon coalescence, and are resistant to high temperature annealing. Following the careful removal of the host CD lattice from each randomly oriented IC crystal, the guest polymer chains now occupying a much-reduced volume may be somewhat "nematically" oriented, resulting in a collection of randomly oriented "nematic" regions of largely extended and un-entangled coalesced guest chains. The suggested randomly oriented nematic domain organization of guest polymers might explain why even at high temperatures their transformation to randomly-coiling, interpenetrated, and entangled melts might be difficult. In addition, the behaviors and uses of polymers coalesced from their CD-ICs are briefly described and summarized here, and we attempted to draw conclusions from and relationships between their behaviors and the unique chain organizations and conformations achieved upon coalescence.
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Affiliation(s)
- Alper Gurarslan
- Fiber & Polymer Science Program, College of Textiles, North Carolina State University, Raleigh, NC 27606-8301, USA.
| | - Abhay Joijode
- Fiber & Polymer Science Program, College of Textiles, North Carolina State University, Raleigh, NC 27606-8301, USA.
| | - Jialong Shen
- Fiber & Polymer Science Program, College of Textiles, North Carolina State University, Raleigh, NC 27606-8301, USA.
| | - Ganesh Narayanan
- Fiber & Polymer Science Program, College of Textiles, North Carolina State University, Raleigh, NC 27606-8301, USA.
| | - Gerry J Antony
- Fiber & Polymer Science Program, College of Textiles, North Carolina State University, Raleigh, NC 27606-8301, USA.
| | - Shanshan Li
- Fiber & Polymer Science Program, College of Textiles, North Carolina State University, Raleigh, NC 27606-8301, USA.
| | - Yavuz Caydamli
- Fiber & Polymer Science Program, College of Textiles, North Carolina State University, Raleigh, NC 27606-8301, USA.
| | - Alan E Tonelli
- Fiber & Polymer Science Program, College of Textiles, North Carolina State University, Raleigh, NC 27606-8301, USA.
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Ye HM, Yao SF. Supernucleating Role of Poly(ω-pentadecalactone) during the Crystallization of Poly(ε-caprolactone) Composites. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.7b03322] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Hai-Mu Ye
- State
Key Laboratory of Heavy Oil, China University of Petroleum, Beijing 102249, People’s Republic of China
- Department
of Materials Science and Engineering, College of Science, China University of Petroleum, 102249 Beijing, People’s Republic of China
| | - Shu-Fang Yao
- Department
of Materials Science and Engineering, College of Science, China University of Petroleum, 102249 Beijing, People’s Republic of China
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Enhancing Stereocomplexation Ability of Polylactide by Coalescing from Its Inclusion Complex with Urea. Polymers (Basel) 2017; 9:polym9110592. [PMID: 30965892 PMCID: PMC6418699 DOI: 10.3390/polym9110592] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 11/04/2017] [Accepted: 11/09/2017] [Indexed: 11/16/2022] Open
Abstract
In this study, polylactide/urea complexes were successfully prepared by the electrospinning method, then the host urea component was removed to obtain a coalesced poly(l-lactide) (PLLA)/poly(d-lactide) (PDLA) blend. The crystallization behavior of the coalesced PLLA/PDLA blend (c-PLLA/PDLA) was studied by a differential scanning calorimeter (DSC) and Fourier transform infrared (FTIR) spectroscopy. The c-PLLA/PDLA was found to show better crystallization ability than normal PLLA/PDLA blend (r-PLLA/PDLA). More interestingly, the c-PLLA/PDLA effectively and solely crystallized into stereocomplex crystals during the non-isothermal melt-crystallization process, and the reason was attributed to the equally-distributing state of PLLA and PDLA chains in the PLLA/PDLA/urea complex, which led to good interconnection between PLLA and PDLA chains when the urea frameworks were instantly removed.
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Han L, Xu H, Wang B, Sui X, Zhang L, Zhong Y, Mao Z. Preparation and characterization of biodegradable poly(ϵ-caprolactone) self-reinforced composites and their crystallization behavior. POLYM INT 2017. [DOI: 10.1002/pi.5413] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Lei Han
- Key Laboratory of Science and Technology of Eco-textiles, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai PR China
| | - Hong Xu
- Key Laboratory of Science and Technology of Eco-textiles, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai PR China
| | - Bijia Wang
- Key Laboratory of Science and Technology of Eco-textiles, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai PR China
| | - Xiaofeng Sui
- Key Laboratory of Science and Technology of Eco-textiles, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai PR China
| | - Linping Zhang
- Key Laboratory of Science and Technology of Eco-textiles, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai PR China
| | - Yi Zhong
- Key Laboratory of Science and Technology of Eco-textiles, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai PR China
| | - Zhiping Mao
- Key Laboratory of Science and Technology of Eco-textiles, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai PR China
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Ye HM, Chen XT, Liu P, Wu SY, Jiang Z, Xiong B, Xu J. Preparation of Poly(butylene succinate) Crystals with Exceptionally High Melting Point and Crystallinity from Its Inclusion Complex. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00656] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
| | | | | | - Shu-Yi Wu
- Advanced
Materials Laboratory of Ministry of Education, Department of Chemical
Engineering, Tsinghua University, 100084 Beijing, P. R. China
| | - Zhiyong Jiang
- State
Key Laboratory of Polymer Physics and Chemistry, Changchun Institute
of Applied Chemistry, Chinese Academy of Science, University of Chinese Academy of Science, Renmin Street 5625, 130022 Changchun, P. R. China
| | - Bijin Xiong
- State
Key Laboratory of Polymer Physics and Chemistry, Changchun Institute
of Applied Chemistry, Chinese Academy of Science, University of Chinese Academy of Science, Renmin Street 5625, 130022 Changchun, P. R. China
| | - Jun Xu
- Advanced
Materials Laboratory of Ministry of Education, Department of Chemical
Engineering, Tsinghua University, 100084 Beijing, P. R. China
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Han L, Xu H, Sui X, Zhang L, Zhong Y, Mao Z. Preparation and properties of poly(ε-caprolactone) self-reinforced composites based on fibers/matrix structure. J Appl Polym Sci 2017. [DOI: 10.1002/app.44673] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lei Han
- Key Lab of Science and Technology of Eco-textile, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai 201620 People's Republic of China
| | - Hong Xu
- Key Lab of Science and Technology of Eco-textile, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai 201620 People's Republic of China
| | - Xiaofeng Sui
- Key Lab of Science and Technology of Eco-textile, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai 201620 People's Republic of China
| | - Linping Zhang
- Key Lab of Science and Technology of Eco-textile, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai 201620 People's Republic of China
| | - Yi Zhong
- Key Lab of Science and Technology of Eco-textile, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai 201620 People's Republic of China
| | - Zhiping Mao
- Key Lab of Science and Technology of Eco-textile, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; Shanghai 201620 People's Republic of China
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Ravindran P, Vasanthan N. Formation of Poly(3-hydroxybutyrate) (PHB) Inclusion Compound with Urea and Unusual Crystallization Behavior of Coalesced PHB. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b00387] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pavithran Ravindran
- Department of Chemistry, Long Island University, One
University Plaza, Brooklyn, New York 11201, United States
| | - Nadarajah Vasanthan
- Department of Chemistry, Long Island University, One
University Plaza, Brooklyn, New York 11201, United States
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Gurarslan A, Caydamli Y, Shen J, Tse S, Yetukuri M, Tonelli AE. Coalesced poly(ε-caprolactone) fibers are stronger. Biomacromolecules 2015; 16:890-3. [PMID: 25615714 DOI: 10.1021/bm501799y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Melt-spun fibers were made from poly(ε-caprolactone) (PCL) coalesced from stoichiometric inclusion complex crystals formed with host urea. Melting and crystallization behaviors, mechanical properties, and the birefringence of undrawn and cold-drawn fibers were investigated. Undrawn coalesced PCL fibers were observed to have 500-600% higher moduli than undrawn as-received (asr) PCL fibers and a modulus comparable to drawn asr PCL fibers. Drawn coalesced PCL fibers have the highest crystallinity, orientation, and 65% higher moduli than drawn asr PCL fibers. Drawn coalesced PCL fibers have only a 5% higher crystallinity than drawn asr PCL fibers, yet they have 65% higher moduli and lower elongation at break values. Clearly, the intrinsic alignment of the coalesced polymers is the reason for their higher moduli and lower elongation, as confirmed by the birefringence observed in drawn coalesced and asr-PCL fibers. The improved mechanical properties of coalesced PCL fibers make them a better candidate for use in tissue engineering as scaffolds.
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Affiliation(s)
- Alper Gurarslan
- Fiber & Polymer Science Program College of Textiles, North Carolina State University , Campus Box 8301, 2401 Research Drive, Raleigh, North Carolina 27695-8301, United States
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Non-Stoichiometric Polymer-Cyclodextrin Inclusion Compounds: Constraints Placed on Un-Included Chain Portions Tethered at Both Ends and Their Relation to Polymer Brushes. Polymers (Basel) 2014. [DOI: 10.3390/polym6082166] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Morphology and crystalline structure of inclusion compounds formed between poly(ethylene glycol) and urea. CHINESE JOURNAL OF POLYMER SCIENCE 2014. [DOI: 10.1007/s10118-014-1496-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Harmata AJ, Ward CL, Zienkiewicz KJ, Wenke JC, Guelcher SA. Investigating the Effects of Surface-Initiated Polymerization of ε-Caprolactone to Bioactive Glass Particles on the Mechanical Properties of Settable Polymer/Ceramic Composites. JOURNAL OF MATERIALS RESEARCH 2014; 29:2398-2407. [PMID: 25798027 PMCID: PMC4364443 DOI: 10.1557/jmr.2014.254] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Injectable bone grafts with strength exceeding that of trabecular bone could improve the management of a number of orthopaedic conditions. Ceramic/polymer composites have been investigated as weight-bearing bone grafts, but they are typically weaker than trabecular bone due to poor interfacial bonding. We hypothesized that entrapment of surface-initiated poly(ε-caprolactone) (PCL) chains on 45S5 bioactive glass (BG) particles within an in situ-formed polymer network would enhance the mechanical properties of reactive BG/polymer composites. When the surface-initiated PCL molecular weight exceeded the molecular weight between crosslinks of the network, the compressive strength of the composites increased 6- to 10-fold. The torsional strength of the composites exceeded that of human trabecular bone by a factor of two. When injected into femoral condyle defects in rats, the composites supported new bone formation at 8 weeks. The initial bone-like strength of BG/polymer composites and their ability to remodel in vivo highlight their potential for development as injectable grafts for repair of weight-bearing bone defects.
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Affiliation(s)
- Andrew J Harmata
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235 ; Center for Bone Biology, Vanderbilt Medical Center, Nashville, TN 37232
| | - Catherine L Ward
- Orthopaedic Task Area, U.S. Army Institute of Surgical Research, San Antonio, TX 78234
| | - Katarzyna J Zienkiewicz
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
| | - Joseph C Wenke
- Orthopaedic Task Area, U.S. Army Institute of Surgical Research, San Antonio, TX 78234
| | - Scott A Guelcher
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235 ; Center for Bone Biology, Vanderbilt Medical Center, Nashville, TN 37232 ; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37235
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Tonelli AE. Restructuring polymers via nanoconfinement and subsequent release. Beilstein J Org Chem 2012; 8:1318-32. [PMID: 23019466 PMCID: PMC3458756 DOI: 10.3762/bjoc.8.151] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 07/13/2012] [Indexed: 11/23/2022] Open
Abstract
During the past several years my students and I have been utilizing certain small-molecule hosts to create nanostructured polymers. This is accomplished by first forming noncovalently bonded inclusion complexes (ICs) between these small-molecule hosts and guest polymers, followed by the careful removal of the host crystalline lattice to obtain a coalesced bulk polymer. We have repeatedly observed that such coalesced polymer samples behave distinctly from those produced from their solutions or melts. Coalesced amorphous homopolymers exhibit higher glass-transition temperatures, while crystallizable homopolymers coalesced from their ICs display higher melting and crystallization temperatures, and sometimes different crystalline polymorphs. When ICs are formed with block copolymers or with two or more different homopolymers, the resulting coalesced samples can exhibit intimate mixing between the copolymer blocks, or between entire homopolymer chains. Each of the distinct behaviors observed for polymers coalesced from their ICs is a consequence of the structural organization of the polymer-host-ICs. Polymer chains in host-IC crystals are confined to occupy narrow channels (diameter ~0.5-1.0 nm) formed by the small-molecule hosts around the included guest polymers during IC crystallization. This results in the separation and high extension of the included guest polymer chains, which leads, following the careful removal of the host molecule lattice, to unique behaviors for the bulk coalesced polymer samples. Apparently, substantial degrees of the extended and unentangled natures of the IC-included chains are retained upon coalescence. In this review we summarize the behaviors and uses of coalesced polymers, and attempt to draw conclusions on the relationship between their behavior and the organization/structures/conformations of the constituent polymer chains achieved upon coalescence from their ICs.
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Affiliation(s)
- Alan E Tonelli
- Fiber & Polymer Science Program, North Carolina State University, Campus Box 8391, Raleigh, NC, 27695-8301, USA
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