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The Effect of Reaction Conditions on the Synthesis of Thermoplastic Elastomers Containing Polyalloocimene, polyisobutylene and Tapered Blocks

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Chinese Journal of Polymer Science 2019年第9期37卷 884-890页

作者： Jozsef Kantor Judit E. Puskas Gabor Kaszas Department of Chemical and Biomolecular Engineering The University of Akron Akron OH 44325 USA Department of Food Agricultural and Biological Engineering (1/1/2019) The Ohio State University Wooster OH 44691 USA PolyFiberMatrix LLC 2295 W. Market St. Suite D. Akron OH 44313 USA

This work investigates the effect of reaction conditions on the copolymerization of isobutylene (IB) with alloocimene (Allo) in methyl chloride (MeCl) using AlCh and ethylaluminum dichloride (EtAlCh) as coinitiators and adventitious moisture as the initiator. Both AlCh and EtAlCb produced high molecular weight (Mn > 1.0 x 10^5 g/mol) thermoplastic elastomers (TPEs) with good mechanical properties in short reaction time (< 10 min). These unique TPEs have unsaturations in the end blocks, leading to easy functionalization and/or crosslinking.

关键词： polyisobutylene Alloocimene Triblock copolymer Carbocationic polymerization

Amphiphilic Graft Copolymers of Hydroxypropyl Cellulose Backbone with Nonpolar polyisobutylene Branches

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Chinese Journal of Polymer Science 2021年第8期39卷 1029-1039,I0007页

作者： Jin-Rui Deng Cong-Lei Zhao Zhi-Tao Wei Yi-Xian Wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China

The novel amphiphilic graft copolymers with hydrophilic hard polar hydroxypropyl cellulose(HPC)backbone and hydrophobic soft nonpolar polyisobutylene(PIB)branches have been successfully synthesized through nucleophilic substitution reaction of living PIB chains carrying oxonium ions with the-OH groups along HPC *** PIB branch length in the graft copolymers could be designed by living cationic polymerization and the grafting density could be adjusted by PIB+/-OH molar *** living PIB chains carrying oxonium ion were prepared by transformation of allyl bromide end groups in the presence of AgCI0_(4) and silver nanoparticles(3.2±0.3 nm,0.7 wt%-1.8 wt%)generated in situ from *** phase-separation morphology was formed in the graft copolymers due to their incompatibility between backbone and *** hydrophilicity on the surface of graft copolymer films could be turned to hydrophobicity by increasing grafting density or/and length of PIB *** soft PIB segments in graft copolymers provided an unique surface wa self-assembly for ant卜protein adsorption against bovine serum albumin.A small amount of Ag nanoparticles in the copolymers contributed to good antibacterial activities against Staphylococcus aureus or Escherichia coli.

关键词： Hydroxypropyl cellulose polyisobutylene Graft copolymer Cationic polymerization

Biocompatible,Hemocompatible and Antibacterial Acylated Dextran-g-polyisobutylene Graft Copolymers with Silver Nanoparticles

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Chinese Journal of Polymer Science 2021年第12期39卷 1550-1561页

作者： Cong-Lei Zhao Yu-Zhuang Gao Meng-Ying Wu Hang-Tian Zhang Yi-Xian Wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China

The novel amphiphilic acylated dextran-g-polyisobutylene(AcyDex-g-PIB)graft copolymers with different branch lengths(A4nPtB,2600-5800 g/mol)and grafti ng numbers(GN,5-28 per 1000 Dex mono saccharide)were successfully synthesized via the nu cleophilic substitution of the hydroxyl(-OH)side groups along AcyDex backb one by the living PIB-THF4+chai ns prepared through cati onic polymerizatio *** crystallizati on of AcyDex backb one in AcyDex-g-PIB graft copolymers was con fined due to the prese nee of PIB branches and the morphology changed from short rod-like crystals to fragment-like crystals with increasing Mn P|B and *** obvious microphase separation occurred due to the incompatibility between hard AcyDex backbone and soft PIB ***-g-PIB graft copolymers exhibit excellent biocompatibility towards HeLa cells and good hemocompatibility with red blood cells(RBCs),both of which increase with increasing *** in creases of water con tact angle and roughness on the surface of the graft copolymers with in creasi ng A4nP|B and GN manifest the anti-protein adsorption *** amphiphilic AcyDex-g-PIB graft copolymers could self-assemble in aqueous solution into nanospheres,which can be used as pH-sensitive drug carriers and can release 100%of the loaded drug within 72 h at pH=***-g-PIB graft copolymers bearing silver nanoparticles(Ag-NPs,0.8 wt%-3.9 wt%,4.5-9.5 nm)show good antibacterial *** kind of amphiphilic graft copolymer would have a promising prospect in biological and medical fields.

关键词： Dextran polyisobutylene Cationic polymerization Graft copolymer Biomedical application

SYNTHESIS OF pH-RESPONSIVE AMPHIPHILIC DIBLOCK COPOLYMERS CONTAINING polyisobutylene via OXYANION-INITIATED POLYMERIZATION AND THEIR MULTIPLE SELF-ASSEMBLY MORPHOLOGIES

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Chinese Journal of Polymer Science 2013年第2期31卷 218-231页

作者： Huai-chao Wang Ming-zu Zhang 倪沛红 Jin-lin He Ying Hao Yi-xian Wu College of Chemistry Chemical Engineering and Materials Science Soochow University Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Soochow University State Key Lab of Chemical Resource Engineering Beijing University of Chemical Technology

Two pH-responsive amphiphilic diblock copolymers, namely polyisobutylene-block-poly[2-（N,N- dimethylamino）ethyl methaerylate] （PIB-b-PDMAEMA） and polyisobutylene-block-poly（metharylic acid）（PIB-b-PMAA）, were synthesized via oxyanion-initiated polymerization, and their multiple self-assembly behaviors have been studied. An exo-01efin-terminated highly reactive polyisobutylene （HRPIB） was first changed to hydroxyl-terminated PIB （PIB-OH） via hydroboration-oxidation of C =C double bond in the chain end, and then reacted with KH to yield a potassium alcoholate of PIB （PIB-O-K＋）. PIB-O-K＋ was immediately used as a macroinitiator to polymerize DMAEMA monomer, resulting in a cationic diblock copolymer PIB-b-PDMAEMA. With the similar synthesis procedure, the anionic diblock copolymer PIB-b- PMAA could be prepared via a combination of oxyanion-initiated polymerization of tert-butyl methacrylate （tBMA） and subsequent hydrolysis of tert-butyl ester groups in PtBMA block. The functional PIB and block copolymers have been fully characterized by 1H-NMR, FT-IR spectroscopy, and gel permeation chromatography （GPC）. These samples allowed us to systematically investigate the effects of block composition on the pH responsivity and various self-assembled morphologies of the copolymers in THF/water mixed solvent. Transmission electron microscopy （TEM） images revealed that these diblock copolymers containing small amount of original PIB without exo-olefin-terminated group are able to self-assemble into micelles, vesicles with different particle sizes and cylindrical aggregates, depending on various factors including block copolymer composition, solvent polarity and pH value.

关键词： Oxyanion-initiated polymerization polyisobutylene Stimuli responsivity Amphiphilic copolymer Self- assembly.

SYNTHESIS OF polyisobutylene WITH SEC-ARYLAMINO TERMINAL GROUP BY COMBINATION OF CATIONIC POLYMERIZATION WITH ALKYLATION

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Chinese Journal of Polymer Science 2009年第4期27卷 551-559页

作者：吴一弦 Beijing University of Chemical Technology State Key Laboratory of Chemical Resource Engineering

The highly reactive polyisobutylenes(PIBs) withα-double bonds(87.5 mol%) or tert-chloro(tert-Cl) groups(95 mol%) could be prepared via the cationic polymerization of isobutylene(IB) coinitiated by BF_3 or TiCl_4 *** Friedel-Crafts alkylation of diphenylamine(DPA) with the highly reactive PIB withα-double bonds was further conducted under different conditions,such as at different alkylation temperature,in the mixed solvents of CH_2Cl_2/n-hexane with different solvent polarity and at DPA concentr...

关键词： polyisobutylene Cationic polymerization Diphenylamine Alkylation

The use of polyisobutylene-based polymers in ophthalmology

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Bioactive Materials 2022年第4期7卷 185-194页

作者： Leonard Pinchuk Distinguished Research Professor of Biomedical Engineering University of MiamiBiomedical Engineering Dept.13704 SW 92nd CourtMiami33176FLUnited States Founder and Senior Vice President InnFocusInc.a Santen companyMiamiFLUnited States

A novel polyolefin called poly(styrene-block-isobutylene-block-styrene)(“SIBS”)originated from Joseph ***’s laboratory at the University of Akron(Akron,Ohio,United States)and was developed as a biomaterial for long-term implant applications by the *** has no cleavable groups on its backbone or sidechains,is comprised predominantly of alternating secondary and quaternary carbons on its backbone,which prevents embrittlement and cracking under flexion,and undergoes multiple purification steps which renders it extremely biocompatible and well-suited for long-term applications in the *** article explores two ophthalmic devices;1)the PRESERFLO®MicroShunt(Santen Pharmaceutical ***.,Osaka,Japan)made from SIBS that lowers intraocular pressure to thwart progression of vision loss from glaucoma,and 2)a novel intraocular lens(IOL)made from crosslinked polyisobutylene,which is under-development by Xi’an Eyedeal Medical Technology Co.,Ltd.(Xi’an,China)that does not glisten nor cloud over time,as do most conventional IOLs.

关键词： Poly(styrene-block-isobutylene-block-styrene) SIBS Glaucoma MicroShunt Intraocular Lens IOL polyisobutylene Cataract

Controlling Heat Transfer for the Manufacturing of High Molecular Weight polyisobutylene via Formation of Micelles

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Chinese Journal of Polymer Science 2019年第9期37卷 898-902页

作者： Szilard Csihony Nicole Janssen Klaus Mühlbach Advanced Materials & Systems

An alternative cationic polymerization method is developed to produce high molecular weight polyisobutylene (HM-PIB) with molecular weights above 5×10^5g/mol. The method involves micelle formation via functionalized low molecular weight polyisobutylene (LM-PIB) in non-polar solvent. One end of LM-PIB is modified with an imidazolium-containing ionic group, which together with the anion (eg. Al2Cl7) works as Lewis acid. While the monomer isobutylene dissolves readily in non-polar solvent, polymerization can occur only within the micelle, which affords stable HM-PIB particles. HM-PIB with a molecular weight (MW) close to 1 × 10^6 g/mol was produced successfully with the described method.

关键词： Cationic polymerization High molecular weight polyisobutylene Micelle

Synthesis and Properties of Hydroxytelechelic polyisobutylenes by End Capping with tert-Butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane

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Chinese Journal of Polymer Science 2019年第9期37卷 936-942页

作者： Jing Li Kang-Da Wu Huang Shan Jing-Han Zhang Ming Zhao Guang-Bi Gong Wen-Li Guo Yi-Bo Wu College of Materials Science & Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China Lanzhou Petrochemical Research Center Petrochina Lanzhou 730060 China Beijing Key Laboratory of Specialty Elastomer Composite Materials Beijing Institute of Petrochemical Technology Beijing 102617 China

The low-activity cationic monomer tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane was synthesized by Grignard reaction and hydroxyl-protection reaction. Living polyisobutylene chains were initially synthesized by controlled cationic polymerization and then capped with tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane. The hydrolysis of these polyisobutylenes end capped with tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane gave rise to hydroxytelechelic polyisobutylene. NMR analysis confirmed that the hydrolysis was complete. Results also showed that a low polymerization temperature favored the participation of tert-butyl-dimethyl-(4- methyl-pent-4?enyloxy)-silane in the end-capping reaction. Moreover, polyisobutylene-based polyurethane exhibited greater acid resistance than commercial polyurethane.

关键词： Carbocationic polymerization polyisobutylene Hydrolysis polyisobutylene-based polyurethane

Cationic Polymerization of Isobutylene and C4 Mixed Feed Using Complexes of Lewis Acids with Ethers: A Comparative Study

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Chinese Journal of Polymer Science 2019年第9期37卷 891-897页

作者： Dmitriy I. Shiman Ivan A. Berezianko Irina V. Vasilenko Sergei V. Kostjuk Research Institute for Physical Chemical Problems of the Belarusian State University 14 Leningrads kaya St. Minsk 220006 Belarus Department of Chemistry Belarusian State University 14 Leningradskaya st. Minsk 220006 Belarus Sechenov First Moscow State Medical University Institute for Regenerative Medicine 8-2 Trubetskaya st. Moscow 119991 Russia

The cationic polymerization of C4 mixed feed and isobutylene co-initiated by AlCl3xOiPr2,iBuAlC12xnOiPr2, and [emim]Cl- FeCl3xnOiPr2 ([emim]Cl: 1 -ethyl-3-methylimidazolium chloride) has been investigated. AlCl3xOiPr2 co-initiated cationic polymerization of C4 mixed feed proceeds at a lower rate than polymerization of isobutylene affording polymers with higher molecular weight. Complexes of iBuAlCh with di isopropyl ether of different compositions are more suitable co-initiators than AlCl3xOiPr2 for the synthesis of highly reactive polyisobutylene (HR PIB) from C4 mixed feed due to their higher activity in the polymerization as well as possibility to prepare polyisobutylenes with lower molecular weight and higher content of exo-olefin end groups. However, iBuA1C12 needs activating via addition of external water (initiator) and/or interaction with salts hydrates in order to increase the reaction rate and the saturated monomer conversion.[Emim]Cl-FeC13/iPr2O is a quite promising catalyst for the preparation of HR PIB with high exo-olefin end group content (> 80%) and relatively low polydispersity (Mw/Mn < 2.8) via cationic polymerization of C4 mixed feed. The sonication of reaction mixture in case of using [emim]Cl-FeCh allowed increasing the reaction rate and decreasing the molecular weight.

关键词： Cationic polymerization Isobutylene C4 mixed feed Highly reactive polyisobutylene