寡聚乳酸改性葡聚糖的合成及表征

设计了两种基于寡聚L-乳酸(OLL)改性葡聚糖的工艺路线:路线Ⅰ为OLL末端羟基活化后接枝葡聚糖;路线Ⅱ为在亲核试剂及偶合剂的存在下,OLL末端羧基接枝葡聚糖.研究表明,固定OLL与葡聚糖摩尔比,延长反应时间有利于提高路线Ⅰ的产品得率,而对路线Ⅱ中的产品得率几乎没有影响.1HNMR,IR,UV表征改性后产物显示OLL在葡聚糖上的接枝率(葡聚塘的100个葡萄糖单元上OLL的数目)可以通过调节反应物摩尔比得到有效的控制.     

电活性聚芳醚酮类环状分子的合成和性质

将电活性苯胺四聚体链段引入聚芳醚酮类刚性大环分子中, 得到了含电活性苯胺链段的聚芳醚酮类大环状分子低聚物C-1, 并通过循环伏安和紫外滴定法证明了这种新型环状分子具有电活性.     

One-pot method of preparing novel macrocyclic(thio arylene) oligomers

A series of macrocyclic(thio arylene) oligomers were synthesized under high dilution conditions by reacting diphenyl ether, diphenyl, diphenyl disulfide or diphenyl methane with dichloro disulfide in the presence of trace amount of iron powder by a one-step method. The composition of these macrocyclic oligomers was analyzed by MALDI-TOF technology, and the experimental results showed that the cyclics were a mixture with repeating units separated by one to seven sulfur atoms. These macrocyclics can undergo ring-opening polymerization to form linear polymers under mild conditions. The glass transition temperatures of produced polymers varied with the sulfur content.     

Preparation of telechelic oligomers by controlled thermal degradation of isotactic poly(1-butene) and poly(propylene-ran-1-butene)

It was found that telechelic isotactic oligo(1-butene) and telechelic oligo(propylene-ran-1-butene) could be isolated as nonvolatile oligomers from polymer residues resulting from the thermal degradation of isotactic poly(1-butene) and poly(propylene-ran-1-butene), respectively. Their structures were determined by ¹H and ¹³C NMR with attention being paid to their reactive end groups. The maximum average number of terminal vinylidene groups per molecule (f_TVD) was 1.8, indicating that about 80 mol% were α,ω-diene oligomers having two terminal vinylidene groups. This useful new telechelic oligomer had a lower polydispersity than the original polymer, in spite of its lower molecular weight and T_m. The composition of end groups of nonvolatile oligomers obtained by thermal degradation of poly(propylene-ran-1-butene) could be explained by the differences in bond dissociation energy and activation energy of elementary reactions during thermal degradation, based on the monomer composition of the original polymer.     

Syntheses and evaluation of novel biodegradable amino acid based anhydride polymer resins and composites

A novel synthetic biodegradable oligomer based upon methacrylated aminocaproyl maleamic acid (MACMA), was synthesized and characterized. Injectable and in situ crosslinkable polymer networks were formulated by copolymerization of MACMA with triethyleneglycol dimethacrylate (TEGDMA). In addition, composites composed of MACMA, TEGDMA and beta-tricalcium phosphate (β-TCP) were prepared. The networks and composites were initiated by photo- and redox-polymerization, respectively. The initial compressive (CS) and diametral tensile strengths (DTS) of these materials were determined and used to evaluate the effects of MACMA/TEGDMA ratios on the degradation behavior of the materials. The neat resin networks exhibited initial CS values ranging from 6.7 to 284.2 MPa and the composites demonstrated initial DTS values ranging from 2.8 to 20.8 MPa and CS values ranging from 19.1 to 119.5 MPa. During the course of degradation the polymer neat resins lost 51%, 69% and 61% of their initial CS after 3 weeks for the MACMA/TEGDMA ratios at 25/75, 50/50 and 75/25, respectively. The resin with the MACMA/TEGDMA ratio of 75/25 completely degraded after 6 months. The composite with the MACMA/TEGDMA ratio of 25/75 exhibited a significant increase in CS after an initial decrease for 7 days and then lost 57% of its initial CS after 3 months. The composite composed of poly(MACMA) homopolymer showed a complete degradation after 21 days.     

用差减红外光谱分峰法测定乙丙齐聚物中端羟基的微结构

合成了端羟基乙丙齐聚物。用差减红外光谱对端羟基进行了分析。扣除了溶剂中三氯甲烷的干扰,用RUN.CAPR程序进行分峰,以正戊醇-1、3-甲基丁醇-1和丁醇-2为模型化合物标定伯、仲羟基吸收峰位置,并进行蜂面积积分,用模型化合物回归处理后得到定量公式:A=15.8667×10~3Cp+0.25674,以此求得乙丙齐聚物中伯、仲羟基的官能度。     

Solid phase synthesis of peptidotriazoles with multiple cycles of triazole formation

Peptidotriazoles, unnatural oligomers with alternating amide and triazole linkages, are synthesized efficiently on solid support. The key transformations involve multiple cycles of 1,2,3-triazole formation, using soluble Cu(I) catalyst and conditions that do not generate precipitate on solid support nor require exclusion of oxygen. Our synthetic protocol will enable the preparation of other unnatural oligomers with multiple triazoles using solid phase methodologies.     

Study on the Surface Photovoltage and Fluorescence Properties of N, N-Bis(4-aminopheny)-1, 4 quinonenediimine Doped with H_4SiW_(12)O_(40)

Polyaniline, especially its acid-dopping composite material, is a kind of important photoelectric material due to its potential application in many fields1~3. However, it seems to be a problem that the polymers exhibit several deficiencies, including chemical and structural imperfections as a result of mislinkage, saturated sites, molecular weight distribution, the presence of the end groups and conformation defects. All of these defects affect the device efficiency and make it difficult to …     

镓皂石的合成、交联及表征

用水热法合成了镓皂石，并用Ａｌ１３齐聚物进行交联．经ＸＲＤ，ＩＲ，ＭＡＳＮＭＲ和元素分析表征，结果显示镓存在于粘土层四面体骨架中，交联剂引入量与层四面体中镓含量有关，层与柱键合可能发生在ＧａＯ４四面体上．     

从端羟基液体聚丁二烯制备的弹性体 Ⅱ.端羟基液体聚丁二烯的分子量分布对弹性体力学性能的影响

本文研究了端羟基液体聚丁二烯(HTPB)的分子量分布对由HTPB,N、N-二(2-羟丙基)苯胺和甲苯二异氰酸酯制备的弹性体的力学性能的影响。研究结果表明,HTPB的多分散指数从1.6增加到2.1,弹性体的抗张强度,100％模量和硬度未见不良影响,而且略有提高。弹性体的永久形变增加较明显。