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Highly active organocatalyst from a trivalent phosphazenium salt for ring-opening copolymerization of epoxides and cyclic anhydrides enhanced by hydrogen bonding interactions

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Science China Chemistry 2024年第9期67卷 3111-3120页

作者： Chunhuan Jiang Junqi Wang Xiaoyu Liu Xiaoxia You Ronglin Zhong Chuanli Ren Zhibo Li Key Laboratory of Biobased Polymer Materials Shandong Provincial Education DepartmentCollege of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130012China

It is highly desirable to develop simple organocatalysts for the controlled ring-opening alternating copolymerization(ROAC)of epoxides and cyclic anhydrides,leading to high molecular weight ***,a phosphazenium salt,namely tri[tris(dimethylamino)phosphoranylidenamino]phosphonium chloride(P_(4)^(+)Cl^(-)),is developed as a catalyst for the ROAC of epoxides and cyclic ***,the combination of P_(4)^(+)Cl^(-)with a protonic initiator,such as 1,4-benzenedimethanol(BDM)exhibited high efficiency in the copolymerization of propylene oxide(PO)and phthalic anhydride(PA).This led to the production of polyester with an exceptional high molecular weight(M_n)of up to 126 k Da,which represented a rare example of poly(PO-alt-PA)with Mnsurpassing 100 k *** that the core P atom is trivalent status and the tris[tris(dimethylamino)]phosphoranyl group will share one proton in the P_(4)^(+)Cl^(-)*** combined with protonic species,the P_(4)^(+)Cl^(-)will not only serve as a proton acceptor but also as a hydrogen bonding donor for the cyclic ***,it was assumed that the P_(4)^(+)plus proton served dual role in mimic of base/urea pair to effectively catalyze ROAC,which was supported by density functional theory(DFT)calculations.

关键词： ring-opening copolymerization organocatalyst epoxides cyclic anhydrides phosphazenium salt

Synthesis of poly(thiourethane-alt-thioester)by alternating ring-opening copolymerization of N-thiocarboxyanhydrides and episulfides

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Science China Chemistry 2024年第9期67卷 3091-3097页

作者： Wei Xiong Tianjun Yue Haiwang Lai Chunyan Lyu Weimin Ren Hua Lu Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116081China

Polythiourethanes(PTU)and polythioesters(PTE)derived from renewable sources are emerging sustainable polymers for their excellent degradability and ***,P(TU-alt-TE)copolymers have been rare and challenging to ***,we report the efficient synthesis of novel P(TU-alt-TE)copolymers via the alternating copolymerization of N-thiocarboxyanhydrides(NTA)/episufides(ES)and provide mechanistic insight into the alternating chain propagation process via density functional theory(DFT)*** incorporation of ESs into traditional peptide backbone is capable of adjusting the glass transition temperature below thermal decomposition temperature,which confers better thermal processability by regulating the rigidity of the backbone and the hydrogen bond interaction among the polymer *** PTUs with tailored properties are accessible by altering the feeding ratio of NTAs and(bifunctional)***,the thiourethane in the backbone can endow interesting underwater adhesion properties to the *** the broad scope of NTA and ES monomers,this method is expected to provide a promising and general route to a wide range of P(TU-alt-TE)copolymers with diverse properties.

关键词： poly(thiourethane-alt-thioester) alternating ring-opening copolymerization N-thiocarboxyanhydrides episulfides

Partners in Epoxide copolymerization Catalysis:Approach to High Activity and Selectivity

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Chinese Journal of Polymer Science 2022年第11期40卷 1331-1348页

作者： Xiao-Bing Lu Bai-Hao Ren State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China

The ring-opening alternating copolymerization processes of epoxides with small-molecule monomers,such as carbon dioxide(CO_(2)),carbonyl sulfide(COS)and cyclic anhydrides,are powerful strategies for preparing polymeric materials with degradable carbonate/ester/thiocarbonate main-chain backbone *** catalysts selected for copolymerization processes play crucial roles in determining their reaction rates and productivities,as well as the selectivity,regio-and stereochemistry,compositions,and the molecular weights of their resultant *** processes often generate undesirable byproducts such as polyether or ether linkages dispersed randomly within the copolymer's chain,and/or more thermodynamically stable cyclic *** this account,we outline our efforts of over a dozen years on developing highly active well-defined metal catalysts based on inter-and intra-molecular synergistic strategies to selectively produce completely alternating copolymers from epoxides and various small-molecule *** attention was paid to the enantioselective resolution copolymerization processes of racemic epoxides via regioselective ring-openings,and the asymmetric copolymerization processes of meso-epoxides with CO_(2),COS,or cyclic anhydrides via dissymmetrical ring-openings using multichiral catalytic systems,and affording isotactic copolymers with main-chain *** addition,this account provides a thorough mechanistic understanding of the high reactivities,excellent selectivity,and unprecedented stereochemical controls of these copolymerization systems,mediated by interand intramolecular synergistic catalysis.

关键词： Epoxide ring-opening copolymerization Synergistic catalysis CO_(2) Stereochemistry control

Alternating copolymerization of Epoxides and Isothiocyanates to Diverse Functional Polythioimidocarbonates and Related Block Polymers

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Chinese Journal of Chemistry 2023年第23期41卷 3311-3318页

作者： Xiao-Feng Zhu Xin-Yu Lu Cheng-Kai Xu Yu-Bo Fang Guan-Wen Yang Wei Li Jingdai Wang Guang-Peng Wu MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang310027 China Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhouZhejiang310027 China

Synthesis of diverse polythioimidocarbonates via ring-opening copolymerization of epoxides and isothiocyanates catalyzed by organoboron catalyst was reported *** aromatic and aliphatic isothiocyanates underwent successful copolymerization with terminal and internal epoxides,allowing for the precise tuning of the performance of the resultant copolymers over a broad *** wide scope of available isothiocyanates and epoxides enables the direct construction of sulfur-containing functional polymers featuring both high glass transition temperature and refractive ***,it was observed that aromatic isothiocyanates polymerize much faster than aliphatic ones,and the reactivity difference facilitated the one-step synthesis of block polymers from mixed aromatic isothiocyanates,aliphatic isothiocyanates and epoxides due to the preferential incorporation of aromatic isothiocyanates over the aliphatic analogues during their alternating copolymerization with *** produced polythioimidocarbonates can be used as positive resists for electron beam lithography(sensitivity of 130μC/cm^(2) and contrast of 1.53 for poly(CHO-alt-EITC)).Coupling with their high refractive index(1.58—1.68),polythioimidocarbonates might find functional applications in *** results render ring-opening copolymerization of epoxides and isothiocyanates a facile route to enrich functional polymer library.

关键词： ring-opening copolymerization Metal-free catalysis Sulfur-containing polymers Block polymers Electron beam lithography High refractive index

Fully Chemical Recyclable Poly(γ-butyrolactone)-based Copolymers with Tunable Structures and Properties

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Chinese Journal of Polymer Science 2022年第5期40卷 456-461页

作者： Yi-Huan Liu Xin Yuan Jia-Qi Wu Ming-Xuan Luo Xin Hu Ning Zhu Kai Guo Collegeof Biotechnology and Pharmaceutical Engineering Nanjing Tech UniversityNanjing 211800China Collegeof Materials Science and Engineering Nanjing Tech UniversityNanjing 211800China State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjing 211800China

The emerging chemical recyclable polymers,such as poly(γ-butyrolactone)(PGBL)and poly((R)-3,4-trans six-membered ring-fused GBL)(P((R)-M)),provide a good solution to the plastic ***,these homopolymers suffer from limited structures and ***,we reported a fully chemical recyclable copolymer P(GBL-co-((R)-M))through ring-opening copolymerization(ROCOP)of GBL and(R)-*** employing organomagnesium as the catalyst and regulating the reaction conditions,the chemical structures of copolymers were wellcontrolled(GBL content=13%-78%,Mn=6560-15600 g/mol,DM=1.08-1.59).The resultant P(GBL-co-((R)-M))exhibited fully chemical recyclability,which rapidly and quantitatively depolymerized into initial GBL and(R)-M monomer through *** varying GBL content,tunable thermal properties were achieved for P(GBL-co-((R)-M)).The onset decomposition temperatures of copolymers varied from 193°C to 234°C.A linear evolution of glass transition temperature(T_(g))of P(GBL-co-((R)-M))versus GBL content was obtained as following equation of Tg=-1.06×GBL mol%×100+*** hope that the reported fully chemical recyclable copolymers with tunable structures and properties would serve as the candidate material for sustainable applications.

关键词： Poly(γ-butyrolactone)-based copolymers ring-opening copolymerization Chemical recyclability Organomagnesium

SYNTHESIS OF POLY ( ETHER-URETHANE) CONTAINING PENDANT AMINO GROUP

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Chinese Journal of Polymer Science 1989年第1期7卷 90-96页

作者：吴锦煌孙燕慧冯新德 Department of Chemistry Peking Universtiy

This paper is concerned with the synthesis of poly (ether-urethane) with pendant amino groups. The copolyether produced by ring opening copolymerization of tetrahydrofuran and epibromohydrin was treated with sodium azide in dimethylformamide to form azido substituted copolyether. The poly (ether-urethane) made from it was subjected to reduction reaction to convert azido group to amino group. The stress-strain behavior and dynamic-mechanical properties of poly (ether-urethane) containing pendant amino groups were studied.

关键词： Poly (ether-urethane) ring-opening copolymerization Azide reduction Dynamic-mechanical properties

Synthesis and Properties of Biodegradable Copolymers of 9-Phenyl-2, 4, 8, 10-tetraoxaspiro-[5, 5]undcane-3-one and Ethylene Ethyl Phosphate

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Chinese Chemical Letters 2006年第10期17卷 1365-1368页

作者： Jian XU Zhi Lan LIU Ren Xi ZHUO Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Wuhan 430072

Novel biodegradable copolymer poly（CC-co-EEP） was synthesized by ring-opening copolymerization of cyclic carbonate 9-phenyl-2, 4, 8, 10-tetraoxaspiro-[5, 5]undcane-3-one （CC） and ethylene ethyl phosphate （EEP）. The obtained poly （CC-co-EEP）s were characterized by FTIR, ^1H NMR, ^13C NMR and gel permeation chromatography （GPC）. In vitro hydrolytic degradation of the copolymers were investigated in phosphate buffer solution （pH=7.4）. Hydrophilic phosphate units apparently improved the degradability of poly（carbonate-phosphate）.

关键词： Poly(carbonate-phosphate) ring-opening copolymerization biodegradable polymers.

Measurement of Monomer Reactivity Ratios of D,L-3-Methylglycolide with Glycolide or D,L-Lactide

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Chinese Chemical Letters 2000年第9期11卷 815-818页

作者： Chang Ming DONG Kun Yuan QIU Zhong Wei GU Xin De FENG Department of Polymer Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 National Research Institute for Family Planning, Beijing 100081 Peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China Natl Res Inst Family Plannning Beijing 100081 Peoples R China

For monomer reactivity ratios study, the copolymerization of D,L-3-methylglycolide (MG) with glycolide (GA) or D,L-lactide (LA) was carried out in bulk to a certain low conversion in the presence of stannous octoate at 140 degrees C. The copolymer compositions were determined by H-1 NMR spectroscopy. The monomer reactivity ratios were evaluated by Fineman-Ross method, Kelen-Tudos method and linear least-squares method. The monomer reactivity ratios of D,L-3-methylglycolide and glycolide or D,L-lactide are r(mg)= 0.73, r(ga)= 1.47; r(mg)= 1.71, r(la)= 0.92, respectively.

关键词： D,L-3-methylglycolide glycolide D,L-lactide ring-opening copolymerization monomer reactivity ratios

Polymeric Catalyst with Discrete Distributed Active Centers for Regulating Backbone Structure of Poly(propylene carbonate)

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Chinese Journal of Chemistry 2024年第21期42卷 2599-2606页

作者： Hao Zhou Shunjie Liu Pei Chen Liehang Yang Chunwei Zhuo Fengxiang Gao Xuan Pang Xuesi Chen Xianhong Wang School of Applied Chemistry and Engineering University of Science and Technology of ChinaAnhuiHefei230026 China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchunJilin130022 China

Converting CO_(2) into valuable chemicals is an effective means to alleviate environmental pressure and the depletion of oil *** them,polymers derived from the copolymerization of PO and CO_(2) have been widely studied because of their excellent *** meet the expansion of the application range of CO_(2)-based polymers,regulation of the CU in the polymer is *** on the understanding of the relationship between catalyst synergy and structure,we designed a new generation of polyester-based polymeric catalysts APEPC-R and RPEPC-N with discretely distributed active centers to achieve the synthesis of CO_(2)-based polymers with regulated CU(from 50%to 90%).The discrete arrangement of catalyst active centers was demonstrated by 1H NMR and UV-vis *** from multi-site synergy,high molecular weight(M_(n)>100 kg/mol)CO_(2)-based copolymers with CU among 50%—90%were successfully synthesized and their properties were firstly *** work not only contributes to enriching the scope of the application of CO_(2)-based copolymers but also provides a new platform for the development of a new generation of catalysts.

关键词： Carbon dioxide ring-opening copolymerization Polymeric aluminum porphyrin catalyst Synergy effect Copolymers Homogeneous catalysis