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Roberts CT, Beck SK, Prejean CM, Graul LM, Maitland DJ, Grunlan MA. Star-PCL shape memory polymer (SMP) scaffolds with tunable transition temperatures for enhanced utility. J Mater Chem B 2024; 12:3694-3702. [PMID: 38529581 PMCID: PMC11022546 DOI: 10.1039/d4tb00050a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 03/13/2024] [Indexed: 03/27/2024]
Abstract
Thermoresponsive shape memory polymers (SMPs) prepared from UV-curable poly(ε-caprolactone) (PCL) macromers have the potential to create self-fitting bone scaffolds, self-expanding vaginal stents, and other shape-shifting devices. To ensure tissue safety during deployment, the shape actuation temperature (i.e., the melt transition temperature or Tm of PCL) must be reduced from ∼55 °C that is observed for scaffolds prepared from linear-PCL-DA (Mn ∼ 10 kg mol-1). Moreover, increasing the rate of biodegradation would be advantageous, facilitating bone tissue healing and potentially eliminating the need for stent retrieval. Herein, a series of six UV-curable PCL macromers were prepared with linear or 4-arm star architectures and with Mns of 10, 7.5, and 5 kg mol-1, and subsequently fabricated into six porous scaffold compositions (10k, 7.5k, 5k, 10k★, 7.5k★, and 5k★) via solvent casting particulate leaching (SCPL). Scaffolds produced from star-PCL-tetraacrylate (star-PCL-TA) macromers produced pronounced reductions in Tm with decreased Mnversus those formed with the corresponding linear-PCL-diacrylate (linear-PCL-DA) macromers. Scaffolds were produced with the desired reduced Tm profiles: 37 °C < Tm < 55 °C (self-fitting bone scaffold), and Tm ≤ 37 °C (self-expanding stent). As macromer Mn decreased, crosslink density increased while % crystallinity decreased, particularly for scaffolds prepared from star-PCL-TA macromers. While shape memory behavior was retained and radial expansion pressure increased, this imparted a reduction in modulus but with an increase in the rate of degradation.
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Affiliation(s)
- Courteney T Roberts
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, USA.
| | - Sarah K Beck
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, USA.
| | - C Mabel Prejean
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, USA.
| | - Lance M Graul
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, USA.
| | - Duncan J Maitland
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, USA.
| | - Melissa A Grunlan
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, USA.
- Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, USA
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
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2
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Ahmad Shariff SH, Daik R, Haris MS, Ismail MW. Hydrophobic Drug Carrier from Polycaprolactone- b-Poly(Ethylene Glycol) Star-Shaped Polymers Hydrogel Blend as Potential for Wound Healing Application. Polymers (Basel) 2023; 15:polym15092072. [PMID: 37177238 PMCID: PMC10181117 DOI: 10.3390/polym15092072] [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: 02/13/2023] [Revised: 04/14/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023] Open
Abstract
Blending hydrogel with an amphiphilic polymer can increase the hydrophobic drug loading and entrapment efficiency of hydrogel-based formulations. In this study, a hydrogel formulation with star-shaped polycaprolactone-b-poly(ethylene glycol) (PCL-b-PEG) as the hydrophobic drug cargo is produced. The 4-arm and 6-arm star-shaped PCL are synthesized with different molecular weights (5000, 10,000, 15,000 g/mol) via ROP and MPEG as the hydrophilic segment is attached via the Steglich esterification. FTIR and 1H-NMR analysis showed the presence of all functional groups for homopolymers and copolymers. Mn for all synthesized polymers is close to the theoretical value while GPC spectra showed a monomodal peak with narrow molecular weight distribution (PDI:1.01-1.25). The thermal degradation temperature and crystalline melting point of synthesized polymers increase with the increase in molecular weight and number of arms. All formulations possess high drug loading and entrapment efficiency (>99%) and increase with increasing molecular weight, number of arms, and amount of polymer in the formulations. All formulations showed a sustained drug release pattern with no initial burst, which follows the Korsmeyer-Peppas kinetic model. The polymer hydrogel formulations showed antibacterial activity against E. coli and S. aureus. The hydrogel containing 4-arm PCL15k-PEG is chosen as the best formulation due to its high drug release, good antimicrobial activity, and morphology.
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Affiliation(s)
- Siti Hajar Ahmad Shariff
- Department of Chemistry, Kulliyyah of Science, International Islamic University Malaysia, Kuantan 25200, Malaysia
| | - Rusli Daik
- Department of Chemical Sciences, Faculty of Science & Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia
| | - Muhammad Salahuddin Haris
- Department of Pharmaceutical Technology, Kulliyyah of Pharmacy, International Islamic University Malaysia, Kuantan 25200, Malaysia
- IKOP Pharma Sdn Bhd, Kuantan 25200, Malaysia
| | - Mohamad Wafiuddin Ismail
- Department of Chemistry, Kulliyyah of Science, International Islamic University Malaysia, Kuantan 25200, Malaysia
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3
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Park Y, Jeong D, Jeong U, Park H, Yoon S, Kang M, Kim D. Polarity Nano-Mapping of Polymer Film Using Spectrally Resolved Super-Resolution Imaging. ACS APPLIED MATERIALS & INTERFACES 2022; 14:46032-46042. [PMID: 36103715 DOI: 10.1021/acsami.2c11958] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
With the rapid development of the nanofabrication of polymer materials, the local measurement of the chemical properties of polymer nanostructures has become crucial because they can be highly heterogeneous at the nanoscale. We developed a spectroscopic imaging approach to characterize the nanoscale local polarity of polymer films via spectrally resolved super-resolution microscopy. We demonstrate the capability of the recently developed single-molecule sensing and imaging method to probe the polarity of polymers either inside a polymer matrix or on the external surface of a polymer. The nanoscale polarity sensing capability of our method facilitates the differentiation of various polymer surfaces based on chemical polarities, and it can further differentiate the polarity of functional side chain groups. Moreover, we demonstrate that a two-component polymer mixture can be locally distinguished based on the contrasting polarities of the lateral phase separation, further allowing for the investigation of nanoscale phase separation depending on the composition of the polymer blend film. This approach is anticipated to open the door to further characterizations of various nanocomposite materials.
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Fulati A, Uto K, Iwanaga M, Watanabe M, Ebara M. Smart Shape-Memory Polymeric String for the Contraction of Blood Vessels in Fetal Surgery of Sacrococcygeal Teratoma. Adv Healthc Mater 2022; 11:e2200050. [PMID: 35385611 DOI: 10.1002/adhm.202200050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 03/01/2022] [Indexed: 12/19/2022]
Abstract
Shape-memory polymers (SMPs) are promising materials in numerous emerging biomedical applications owing to their unique shape-memory characteristics. However, simultaneous realization of high strength, toughness, stretchability while maintaining high shape fixity (Rf ) and shape recovery ratio (Rr ) remains a challenge that hinders their practical applications. Herein, a novel shape-memory polymeric string (SMP string) that is ultra-stretchable (up to 1570%), strong (up to 345 MPa), tough (up to 237.9 MJ m-3 ), and highly recoverable (Rf averagely above 99.5%, Rr averagely above 99.1%) through a facile approach fabricated solely by tetra-branched poly(ε-caprolactone) (PCL) is reported. Notably, the shape-memory contraction force (up to 7.97 N) of this SMP string is customizable with the manipulation of their energy storage capacity by adjusting the string thickness and stretchability. In addition, this SMP string displays a controllable shape-memory response time and demonstrates excellent shape-memory-induced contraction effect against both rigid silicone tubes and porcine carotids. This novel SMP string is envisioned to be applied in the contraction of blood vessels and resolves the difficulties in the restriction of blood flow in minimally invasive surgeries such as fetoscopic surgery of sacrococcygeal teratoma (SCT).
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Affiliation(s)
- Ailifeire Fulati
- Research Center for Functional Materials National Institute for Materials Science Tsukuba 3050044 Japan
- Graduate School of Science and Technology University of Tsukuba Tsukuba 3058577 Japan
| | - Koichiro Uto
- Research Center for Functional Materials National Institute for Materials Science Tsukuba 3050044 Japan
| | - Masanobu Iwanaga
- Research Center for Functional Materials National Institute for Materials Science Tsukuba 3050044 Japan
| | - Miho Watanabe
- Department of Pediatric Surgery Graduate School of Medicine Osaka University Osaka 5650871 Japan
| | - Mitsuhiro Ebara
- Research Center for Functional Materials National Institute for Materials Science Tsukuba 3050044 Japan
- Graduate School of Science and Technology University of Tsukuba Tsukuba 3058577 Japan
- Graduate School of Advanced Engineering Tokyo University of Science Tokyo 1258585 Japan
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5
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Li X, Chen H, Xie S, Wang N, Wu S, Duan Y, Zhang M, Shui L. Fabrication of Photo-Crosslinkable Poly(Trimethylene Carbonate)/Polycaprolactone Nanofibrous Scaffolds for Tendon Regeneration. Int J Nanomedicine 2020; 15:6373-6383. [PMID: 32904686 PMCID: PMC7457647 DOI: 10.2147/ijn.s246966] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 07/15/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The treatment of tendon injuries remains a challenging problem in clinical due to their slow and insufficient natural healing process. Scaffold-based tissue engineering provides a promising strategy to facilitate tendon healing and regeneration. However, many tissue engineering scaffolds have failed due to their poor and unstable mechanical properties. To address this, we fabricated nanofibrous polycaprolactone/methacrylated poly(trimethylene carbonate) (PCL/PTMC-MA) composite scaffolds via electrospinning. MATERIALS AND METHODS PTMC-MA was characterized by nuclear magnetic resonance. Fiber morphology of composite scaffolds was evaluated using scanning electron microscopy. The monotonic tensile test was performed for determining the mechanical properties of composite scaffolds. Cell viability and collagen deposition were assessed via PrestoBlue assay and enzyme-linked immunosorbent assay, respectively. RESULTS These PCL/PTMC-MA composite scaffolds had an increase in mechanical properties as PTMC-MA content increase. After photo-crosslinking, they showed further enhanced mechanical properties including creep resistance, which was superior to pure PCL scaffolds. It is worth noting that photo-crosslinked PCL/PTMC-MA (1:3) composite scaffolds had a Young's modulus of 31.13 ± 1.30 MPa and Max stress at break of 23.80 ± 3.44 MPa that were comparable with the mechanical properties of native tendon (Young's modulus 20-1200 MPa, max stress at break 5-100 MPa). In addition, biological experiments demonstrated that PCL/PTMC-MA composite scaffolds were biocompatible for cell adhesion, proliferation, and differentiation.
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Affiliation(s)
- Xing Li
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou510006, People’s Republic of China
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou510006, People’s Republic of China
| | - Honglin Chen
- Institute for Life Science, School of Medicine, South China University of Technology, Guangzhou510006, People’s Republic of China
| | - Shuting Xie
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou510006, People’s Republic of China
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou510006, People’s Republic of China
| | - Ning Wang
- Institute for Life Science, School of Medicine, South China University of Technology, Guangzhou510006, People’s Republic of China
| | - Sujuan Wu
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou510006, People’s Republic of China
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou510006, People’s Republic of China
| | - Yuyou Duan
- Institute for Life Science, School of Medicine, South China University of Technology, Guangzhou510006, People’s Republic of China
| | - Minmin Zhang
- School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou510006, People’s Republic of China
| | - Lingling Shui
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou510006, People’s Republic of China
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou510006, People’s Republic of China
- School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou510006, People’s Republic of China
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Bian Y, Leng X, Wei Z, Wang Z, Tu Z, Wang Y, Li Y. End-Chain Fluorescent Highly Branched Poly(l-lactide)s: Synthesis, Architecture-Dependence, and Fluorescent Visible Paclitaxel-Loaded Microspheres. Biomacromolecules 2019; 20:3952-3968. [PMID: 31490668 DOI: 10.1021/acs.biomac.9b01020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A facile method in combination of "grafting from" and "end-functionalization" was developed for the synthesis of fluorescent highly branched poly(l-lactide)s (PLLA-COU) via ring opening polymerization (ROP) and esterification end-capping. These resulting PLLA-COU with four kinds of architectures, including linear, star, linear-comb, and star-comb structures, were subjected to characterization and application as fluorescent visible paclitaxel-loaded microspheres. The mutual effects of architecture and end-groups on thermal and fluorescence properties, enzymatic degradation, and drug release behaviors were focused. Contrast to linear and star PLLA-COU, two comb-shaped analogues demonstrated higher fluorescence quantum yield, faster drug release, and lower enzymatic degradation rate. All the fluorescent microspheres could maintain fluorescence traceability. The fluorescent PLLA-COU displayed negligible toxicity and good biocompatibility. This work highlights that the fluorescent highly branched poly(l-lactide)s are properties-tailored and used as fluorescent visible drug delivery systems (DDS) for potential theranostic applications.
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Affiliation(s)
- Yufei Bian
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Polymer Science and Engineering, Department of Polymer Science and Engineering, School of Chemical Engineering , Dalian University of Technology , Dalian 116024 , China
| | - Xuefei Leng
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Polymer Science and Engineering, Department of Polymer Science and Engineering, School of Chemical Engineering , Dalian University of Technology , Dalian 116024 , China
| | - Zhiyong Wei
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Polymer Science and Engineering, Department of Polymer Science and Engineering, School of Chemical Engineering , Dalian University of Technology , Dalian 116024 , China
| | - Zefeng Wang
- Department of Chemistry , Lishui University , Lishui 323000 , China
| | - Zhu Tu
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Polymer Science and Engineering, Department of Polymer Science and Engineering, School of Chemical Engineering , Dalian University of Technology , Dalian 116024 , China
| | - Yanshai Wang
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Polymer Science and Engineering, Department of Polymer Science and Engineering, School of Chemical Engineering , Dalian University of Technology , Dalian 116024 , China
| | - Yang Li
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Polymer Science and Engineering, Department of Polymer Science and Engineering, School of Chemical Engineering , Dalian University of Technology , Dalian 116024 , China
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7
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Bian Y, Wei Z, Wang Z, Tu Z, Zheng L, Wang W, Leng X, Li Y. Development of biodegradable polyesters based on a hydroxylated coumarin initiator towards fluorescent visible paclitaxel-loaded microspheres. J Mater Chem B 2019; 7:2261-2276. [PMID: 32254675 DOI: 10.1039/c8tb02952k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In this work, we developed a facile end-functionalization method using hydroxylated coumarin to initiate the ring-opening polymerization of cyclic esters to synthesize a series of fluorescent biodegradable aliphatic polyesters with tailorable properties. The resulting fluorescent functionalized poly(l-lactide) (PLLA-COU), poly(ε-caprolactone) (PCL-COU) poly(δ-valerolactone) (PVL-COU) and poly(trimethylene carbonate) (PTMC-COU) were investigated to evaluate the dependence of fluorescence on the chemical structure and molecular weight of the materials. The differences in the electron withdrawing ability and the density of ester groups are responsible for the changes in the fluorescence quantum yield. Then, two representative biodegradable materials, namely, PLLA-COU and PCL-COU, were used to prepare fluorescent paclitaxel-loaded microspheres. During in vitro drug release, the release rate of the PCL-COU microspheres is dramatically faster than that of the PLLA-COU microspheres due to the difference in the material nature and their surface morphologies, possibly achieving a tunable degradation and release rate for the drug carriers. Fluorescent functionalized polyester microspheres can retain their fluorescence properties and emit bright blue light for fluorescence tracing during the degradation process. Biological evaluations showed that both fluorescent polyesters are devoid of any significant toxicity and have good biocompatibility. The results demonstrated that the obtained fluorescent polyesters are promising for use in traceable and controlled drug delivery with tunable drug release.
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Affiliation(s)
- Yufei Bian
- State Key Laboratory of Fine Chemicals, Department of Polymer Science and Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.
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8
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Gubarev AS, Lezov AA, Senchukova AS, Vlasov PS, Serkova ES, Kuchkina NV, Shifrina ZB, Tsvetkov NV. Diels–Alder Hyperbranched Pyridylphenylene Polymer Fractions as Alternatives to Dendrimers. Macromolecules 2019. [DOI: 10.1021/acs.macromol.8b02388] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | | | - Elena S. Serkova
- Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova str. 28, Moscow 119991, Russia
| | - Nina V. Kuchkina
- Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova str. 28, Moscow 119991, Russia
| | - Zinaida B. Shifrina
- Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova str. 28, Moscow 119991, Russia
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9
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Wang W, Wei Z, Sang L, Wang Y, Zhang J, Bian Y, Li Y. Development of X-ray opaque poly(lactic acid) end-capped by triiodobenzoic acid towards non-invasive micro-CT imaging biodegradable embolic microspheres. Eur Polym J 2018. [DOI: 10.1016/j.eurpolymj.2018.09.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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10
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Wu T, Wei Z, Ren Y, Yu Y, Leng X, Li Y. Highly branched linear-comb random copolyesters of ε-caprolactone and δ-valerolactone: Isodimorphism, mechanical properties and enzymatic degradation behavior. Polym Degrad Stab 2018. [DOI: 10.1016/j.polymdegradstab.2018.07.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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11
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Huang Y, Yu E, Li Y, Wei Z. Novel branched poly(ɛ-caprolactone) as a nonmigrating plasticizer in flexible PVC: Synthesis and characterization. J Appl Polym Sci 2018. [DOI: 10.1002/app.46542] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Yangze Huang
- Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan/School of Chemistry and Chemical Engineering; Shihezi University; Shihezi China
| | - Erlei Yu
- Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan/School of Chemistry and Chemical Engineering; Shihezi University; Shihezi China
- Key Laboratory of Materials-Oriented Chemical Engineering of Xinjiang Uygur Autonomous Region/Engineering Research Center of Materials-Oriented Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering; Shihezi University; Shihezi China
| | - Yanke Li
- Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan/School of Chemistry and Chemical Engineering; Shihezi University; Shihezi China
| | - Zhong Wei
- Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan/School of Chemistry and Chemical Engineering; Shihezi University; Shihezi China
- Key Laboratory of Materials-Oriented Chemical Engineering of Xinjiang Uygur Autonomous Region/Engineering Research Center of Materials-Oriented Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering; Shihezi University; Shihezi China
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Habibu S, Sarih NM, Mainal A. Synthesis and characterisation of highly branched polyisoprene: exploiting the "Strathclyde route" in anionic polymerisation. RSC Adv 2018; 8:11684-11692. [PMID: 35542803 PMCID: PMC9079075 DOI: 10.1039/c8ra00884a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 03/19/2018] [Indexed: 11/26/2022] Open
Abstract
This work aimed at developing a synthetic route towards highly branched poly(isoprene) from commercially available raw materials, in good yield and devoid of microgelation, i.e., to prepare a completely soluble polymer via the versatile technique anionic polymerisation. The polymerisations were conducted under high vacuum conditions using sec-butyllithium as initiator at 50 °C in toluene. Toluene served both as a solvent and as a chain-transfer agent. The polar modifier used was tetramethylethylenediamine (TMEDA), and a commercial mixture of divinylbenzene (DVB) was employed as the branching agent for the "living" poly(isoprenyl)lithium anions. The nature of the reaction was studied on the TMEDA/Li ratio as well as the DVB/Li ratio. The obtained branched polymers were characterised by triple detection size exclusion chromatography (SEC), proton nuclear magnetic resonance spectroscopy (1H NMR), differential scanning calorimetry (DSC) and melt rheology. Broad molecular weight distributions have been obtained for the highly branched polymer products. 1H NMR spectroscopy reveals the dominance of 3,4-polyisoprene microstructure. It was found that the complex viscosities and dynamic moduli of the branched samples were much lower compared to their linear counterparts. The results conform with earlier findings by the "Strathclyde team" for radical polymerisation systems. This methodology has the potential of providing soluble branched vinyl polymers at low cost using the readily available raw materials.
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Affiliation(s)
- Shehu Habibu
- Polymer Research Laboratory, Department of Chemistry, Faculty of Science, University of Malaya 50603 Kuala Lumpur Malaysia
- Department of Chemistry, Faculty of Science, Federal University Dutse PMB 7651 Jigawa State Nigeria
| | - Norazilawati Muhamad Sarih
- Polymer Research Laboratory, Department of Chemistry, Faculty of Science, University of Malaya 50603 Kuala Lumpur Malaysia
| | - Azizah Mainal
- Polymer Research Laboratory, Department of Chemistry, Faculty of Science, University of Malaya 50603 Kuala Lumpur Malaysia
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Tsvetkov NV, Gubarev AS, Lebedeva EV, Lezov AA, Mikhailova ME, Kolomiets IP, Mikusheva NG, Akhmadeeva LI, Kuchkina NV, Serkova ES, Shifrina ZB. Conformational and hydrodynamic parameters of hyperbranched pyridylphenylene polymers. POLYM INT 2016. [DOI: 10.1002/pi.5298] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Nikolay V Tsvetkov
- Department of Physics; St Petersburg State University; Universitetskaya nab. 7-9 St Petersburg 199034 Russia
| | - Alexander S Gubarev
- Department of Physics; St Petersburg State University; Universitetskaya nab. 7-9 St Petersburg 199034 Russia
| | - Elena V Lebedeva
- Department of Physics; St Petersburg State University; Universitetskaya nab. 7-9 St Petersburg 199034 Russia
| | - Alexey A Lezov
- Department of Physics; St Petersburg State University; Universitetskaya nab. 7-9 St Petersburg 199034 Russia
| | - Mariya E Mikhailova
- Department of Physics; St Petersburg State University; Universitetskaya nab. 7-9 St Petersburg 199034 Russia
| | - Igor P Kolomiets
- Department of Physics; St Petersburg State University; Universitetskaya nab. 7-9 St Petersburg 199034 Russia
| | - Nina G Mikusheva
- Department of Physics; St Petersburg State University; Universitetskaya nab. 7-9 St Petersburg 199034 Russia
| | - Lilija I Akhmadeeva
- Department of Physics; St Petersburg State University; Universitetskaya nab. 7-9 St Petersburg 199034 Russia
| | - Nina V Kuchkina
- Nesmeyanov Institute of Organoelement Compounds; Russian Academy of Sciences; Vavilova str. 28 Moscow 119991 Russia
| | - Elena S Serkova
- Nesmeyanov Institute of Organoelement Compounds; Russian Academy of Sciences; Vavilova str. 28 Moscow 119991 Russia
| | - Zinaida B Shifrina
- Nesmeyanov Institute of Organoelement Compounds; Russian Academy of Sciences; Vavilova str. 28 Moscow 119991 Russia
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