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Chinese Chemical Letters 2024年第5期35卷 259-264页

作者： Zhenjie Yang Chenyang Hu xuan pang Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

It is of great interest to make a degradable material widely tailorable to replace petroleum-derived products among diverse ***,we report the construction of a new multi-purpose degradable material for the first time via a simple ternary copolymerization system comprisingε-caprolactone(ε-CL),cyclohexane oxide(CHO)and CO_(2).Under low pressure of 1 bar∼5 bar,the ring-opening polymerization(ROP)ofε-CL and ring-opening copolymerization(ROCOP)of CO_(2) and CHO can simultaneously *** carbonate units are randomly distributed on the polymer *** random terpolymers have controllable molar mass(10-106 kDa)and compositions(4-33 mol%CO_(2)).And the obtained materials show large-span tunability from tough plastic to elastomer and even adhesive.

关键词： Polyesters CO_(2)-derived copolymers Random copolymerization Elastomers Adhesives

Copolymer of lactide and ε-caprolactone catalyzed by bimetallic Schiff base aluminum complexes

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Science China Chemistry 2016年第11期59卷 1384-1389页

作者： Jingwei Yang Zhiqiang Sun Ranlong Duan Lili Li xuan pang Xuesi Chen Department of Materials Science and Engineering Jilin University Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences

A series of copolymers of lactide(LA) and e-caprolactone(ε-CL) with different monomer feed ratios were achieved using three kinds of bimetallic Schiff aluminum complexes as catalysts. The ratios of LA and ε-CL units in different copolymers and the average segments length were determined by NMR analysis. The comparative kinetic study of L-LA/ε-CL and rac-LA/ε-CL copolymerization systems showed that the polymerization rate of LA was faster than ε-CL, and L-LA showed polymerization rate slightly faster than rac-LA. It was inferred that the copolymers achieved by these complexes were gradient copolymers with gradual change in distribution of LA and e-CL units. The thermal properties of these copolymers were characterized by DSC analysis, which showed that the glass transition temperature(Tg) of these copolymers changed regularly according to the pro-portion change of two structural units.

关键词： bimetallic catalyst lactide ε-caprolactone ring opening copolymerization

Schiff base aluminum catalysts containing morpholinomethyl groups in the ring opening polymerization of rac-lactide

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Science China Chemistry 2015年第11期58卷 1741-1747页

作者： Zhijie Guo Ranlong Duan Mingxiao Deng xuan pang Chenyang Hu Xuesi Chen Department of Chemistry Northeast Normal University Key Laboratory of Polymer Ecomaterials Chinese Academy of Sciences Changchun Institute of Applied Chemistry Chinese Academy of Sciences

A series of Schiff base aluminum(III) complexes bearing morpholinomethyl substituents were synthesized. Comprehensive investigations on their stereoselective and kinetic features in the ring opening polymerization of lactide were carried out. The ring opening polymerization proved to be first-order in the catalyst and the monomer. Linear relationships between the numberaverage molecular weight of the polylactide and the monomer conversion were consistent with a well-controlled polymerization. The propagation rate was strongly affected by morpholinomethyl substituents on the salicylaldehyde moiety.

关键词： polylactide morpholinomethyl ring opening polymerization

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren Zhuang-Zhuang Liang Ming-Xin Niu Chen-Yang Hu xuan pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-Tian Zhang Ming-Xin Niu Qi Zhang Chen-Yang Hu xuan pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

Synthesis, Characterization and Application of Methyl 3,5-Disulfo-benzoate Dipotassium Dihydrate as Nucleating Agent for Poly（L-lactide）

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Chemical Research in Chinese Universities 2014年第2期30卷 333-338页

作者： SUN Zhiqiang ZHANG Han pang xuan BIAN Xinchao CHEN Wenqi CHEN Xuesi Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P.R.China

A newly synthesized aromatic sulfonate compound,complex 2 with formula of K2[H3COOC-C6H3（SO3）2]·2H2O（methyl 3,5-disulfo-benzoate dipotassium dihydrate） was synthesized and characterized by elemental analysis,infrared（IR） spectrometry,nuclear magnetic resonance（NMR） and crystal structure ***-crystal X-ray diffraction（XRD） revealed that complex 2 crystallized in the triclinic system with space group P（i）.Complex 2 was used as nucleating agent for poly（L-lactide）（PLLA）.The crystallization of PLLA with powder of complex 2 was investigated by means of differential scanning calorimetry（DSC） and polarized optical microscopy （POM）.The results prove that complex 2 was effective as nucleating agent for *** could accelerate crystallization by reducing the induction time and increasing the density of nuclei in the crystallization *** half-time of crystallization（t0.5） for pure PLLA was about 8 times longer than that of PLLA sample with 1.0％（mass fraction） of complex 2.

关键词： Nucleating agent Crystal structure Poly(L-lactide) Isothermal crystallization

A metal-free coordination–insertion ring-opening polymerization of tetrahydrofuran by the central metalloid bis(pentafluorophenyl)(phenoxy)borane

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Chinese Chemical Letters 2024年第3期35卷 419-422页

作者： Cheng Wu Yixuan Liu Chunsheng Xiao Chenyang Hu xuan pang Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

A new strategy for the metal-free coordination–insertion ring-opening polymerization of tetrahydrofuran by the central metalloid Boron has been first ***(pentafluorophenyl)(phenoxy)borane was used as a catalyst for the polymerization reaction *** polytetrahydrofuran with high molecular weight and narrow molecular weight distribution could be *** proposed mechanism was studied by MALDI-TOF,ESI-MS and O-18 isotope labeling analyses as a metal-free coordination insertion mechanism.

关键词： Metal-free catalyst Bis(pentafluorophenyl)(phenoxy)borane Coordination–insertion mechanism Ring-opening polymerization Polytetrahydrofuran

Progress of photonuclear cross sections for medical radioisotope production at the SLEGS energy domain

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Nuclear Science and Techniques 2023年第12期34卷 77-92页

作者： xuan pang Bao‑Hua Sun Li‑Hua Zhu Guang‑Hong Lu Hong‑Bo Zhou Dong Yang School of Physics Beihang UniversityBeijing 100191China College of Physics Jilin UniversityChangchun 130012China National Basic Science Data Center Beijing 100190China

Photonuclear reactions using a laser Compton scattering(LCS)gamma source provide a new method for producing radioisotopes for medical *** with the conventional method,this method has the advantages of a high specific activity and less *** by the Shanghai Laser Electron Gamma Source(SLEGS),we conducted a survey of potential photonuclear reactions,(γ,n),(γ,p),and(γ,γ')whose cross sections can be measured at SLEGS by summarising the experimental *** general,the data are rare and occasionally ***,theoretical calculations are often used to evaluate the production of medical ***,we verified the model uncertainties of the widely used reaction code TALYS-1.96,using the experimental data of the^(100)Mo(γ,n)^(99)Mo,^(65)Cu(γ,n)^(64)Cu,and^(68)Zn(γ,p)^(67)Cu reactions.

关键词： Medical radioisotope Photonuclear reaction LCS Cross section

The Effect of Oxygen to Salen-Co Complexes for the Copolymerization of PO/C02

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Chinese Journal of Polymer Science 2020年第10期38卷 1124-1130,I0007页

作者： Ran-Long Duan Yan-Chuan Zhou Zhi-Qiang Sun Yue-Zhou Huang xuan pang Xue-Si Chen Key Llaboratory ofPolymer Eomaterials ChangchunIntitute of Apied ChemistyChinese Academy ofSciencesChangchun 130022 China University of Science and Technology of China Hefei 230026 China

A series of Salen-Co(Ⅱ)complexes were synthesized to study the effect of O2 on the catalytic performance of Salen-Co complexes for the copolymerization of PO/CO2 The Salen-Co(Ⅱ) complexes showed low activity on the cyclo addition of CO2 to PO with the aid of a cocatalyst such as PPNCI Unexpectedly,with the addition of O2 the activity of Salen-C(Ⅱ)complexes was obviously increased and 100%cylic carbonate was *** the pressure of O2 increased,the activity of the complex also *** the existence of 02 the activity of the complexes was influenced by their structures and the pressure of 02,and the camplexes with the conjugated structure showed higher *** structures of cocatalyst also played a crucial role as for the change of the activity By altering the electrophilit of Salen-Co(Ⅲ),O2 can also be used as cocatalyst for the copolymerization of PO/CO2。

关键词： Salen-cobalt Epoxides Carbon dioxide Copolymerization

Rational design of new phases of tin monosulfide by first-principles structure searches

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Science China(Physics,Mechanics & Astronomy) 2018年第10期61卷 78-84页

作者： XueTing Wang YuWei Li Yu-xuan pang YuanHui Sun Xin-Gang Zhao Jin-Rui Wang LiJun Zhang Key Laboratory of Automobile Materials of MOE and College of Materials Science and Engineering Jilin University Department of Prosthodontics School and Hospital of Stomatology Jilin University

Tin monosulfide(Sn S), which is composed of earth-abundant elements, holds promise as useful high-performance solar absorber and thermoelectric material. In addition to the ground-state Pnma phase, a series of metastable phases in different crystalline structures have been reported experimentally or theoretically, yet the phase stability diagrams remain elusive. In this article, we provide a comprehensive materials design study of new phases of Sn S using first-principles global optimization structure search calculations. We find that the two-dimensional layered phases are generally more energetically favored than the three-dimensional connected phases. In addition, we discover several new phases with comparable energetics. Four lower-energy phases show clear phonon stabilities evidenced by an absence of imaginary modes. The electronic band structures, carrier transport properties, and absorption spectra of the newly discovered phases are investigated and discussed toward potential applications for solar cells and thermoelectric devices.

关键词： tin monosulfide photovoltaic anisotropic effective masses