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双酚A聚碳酸酯合成新方法的研究进展 总被引:11,自引:0,他引:11
介绍了双酚A聚碳酸酯不同于工业生产中常用的光气法和熔融酯交换法的3种新的合成方法,即固相缩聚法、开环聚合法、完全非光气法的实施方法、主要特点及其新进展,探讨了各种方法存在的主要问题以及对生成的聚合物结构和性能的影响。固相缩聚是由预聚物结晶后在固相缩聚,可以获得结晶型双酚A聚碳酸酯并提高聚合物质量;开环聚合法首先合成环状碳酸酯低聚物再开环聚合得到聚合物,可以获得很高分子质量聚合物;完全非光气法在合成过程中完全避免了光气的使用,环境友好,聚合物质量高,很有发展前景。 相似文献
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以三光气和双酚AF为原料,采用界面缩聚法合成双酚AF型聚碳酸酯,得到最佳的聚合条件为:三光气和双酚AF的物质的量之比为1.3∶3,催化剂三乙胺的用量为双酚AF质量的4%,反应温度为35℃,反应时间为60 min。通过傅里叶变换红外吸收光谱、乌氏黏度计、同步热分析仪、热变形/维卡软化温度测试仪及极限氧指数测定仪对制备样品进行了结构和性能表征,结果表明,制备样品为双酚AF型聚碳酸酯,样品的黏均分子量为32000。玻璃化转变温度为164.3℃,热失重5%的温度为440.8℃,热变形温度为149℃、维卡软化温度为157℃,具有较好的耐热性能;极限氧指数为29.5%,具有较好的阻燃性能。样品经碱溶液浸泡后质量损失率较小,耐碱腐蚀性能较好。样品在很多有机溶剂中都有很好的的溶解性。 相似文献
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采用熔融酯交换法,以双酚S(BPS)及4,4′-二羟基二苯硫醚、双酚A(BPA)、碳酸二苯酯(DPC)为原料合成主链含S的聚碳酸酯(PC)。考察了碱金属的乙酸类化合物及有机胺类化合物的催化作用,结果显示,乙酸钠的催化效果较好,采用碳酸钠、甲醇钠、氢氧化钠为催化剂时,其催化效果与乙酸钠相差不大,催化剂与BPA反应生成的钠盐可能真正起催化作用,其中以碳酸钠为催化剂时所得PC的透明性最好。当BPS,BPA与DPC的物质的量之比为0.1∶0.9∶1.08时,得到数均分子量(Mn)为24 748、重均分子量(Mw)为50 033、多分散系数(PDI)为2.02的PC。随着BPS用量的增加,难以获得高分子量PC,进一步考察了4,4′-二羟基二苯硫醚对合成PC的影响,结果发现,与BPS相比,4,4′-二羟基二苯硫醚的反应活性较好,当其加入量较多甚至全部取代BPA时,仍能得到分子量较高的PC。 相似文献
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A novel flame retardant poly(3-aminopropyl methylsiloxane bis(3-hydroxy phenyl spirocyclic pentaerythritol bisphosphate)) (PSBPBP) in combination with talc was blended into polycarbonate (PC) by melt compounding. The flame retardancy and thermal stability of PC/PSBPBP/talc composites were investigated by limiting oxygen index (LOI) test, UL-94 rating test, thermogravimetric analysis (TGA), Raman spectroscopy (RS), and scanning electron microscope (SEM). The mechanical properties were also measured in this work. Increasing talc content leads to observed improvement on flame retardancy of PC composites. LOI value of PC/PSBPBP/10 wt % talc system was 34, and this system passed V0 rating in the UL-94 test. The char yield at 700°C was 28.2% and the onset decomposition temperature shifted up to 540°C for PC/10% PSBPBP/10% talc system in TGA. In the Raman measure, the R value and G linewidth of PC/PSBPBP with 10 wt % talc composite increased to 1.41 and 65 cm−1 from 1.12 and 43 cm−1 of pure PC, respectively. The Raman results suggest that the char residue of PC/PSBPBP with talc composites was denser and had better barrier property, which is agreement with the SEM results. Besides, talc had no remarkable influence on the mechanical properties of PC/PSBPBP composites. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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Linear alternating polycarbonates optionally containing bisphenol A were prepared from the reaction of linear aliphatic, substituted
aliphatic, cyclic aliphatic and aromatic dihydroxy compounds with bisphenol A bischloroformate at 0–5 °C using a single organic
phase as a reaction medium (e.g., Chloroform or tetrahydrofuran). Twelve aromatic–aromatic and aromatic–aliphatic polycarbonate
polymers were prepared utilizing this procedure. The effect of the experimental conditions on the polymerization was studied
and discussed. The polymers obtained were characterized by IR spectra, 1H and 13C NMR spectra, inherent viscosity, differential scanning calorimetry, and thermogravimetric analyses. 相似文献
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综述了双酚A在环氧树脂、聚碳酸酯和阻燃剂中的应用、国内外产能及消费需求变化,分析了双酚A下游产品的市场发展趋势及最新动态。 相似文献
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以丙氧基化双酚A(D33)、环氧氯丙烷(ECH)和液碱为主要原料,采用两步法工艺合成了丙氧基化双酚A缩水甘油醚(DGEPBA)。考察了原料配比、催化剂用量、反应温度、反应时间等因素对反应的影响。结果表明:开环催化剂三氟化硼-乙醚(BF3-Et2O),质量分数0.1%,D33与ECH的质量比为1∶2.0,反应温度70℃,反应时间2.5h;闭环催化剂苄基三乙基氯化铵质量分数0.2%,D33与NaOH的质量比为1∶2.2,反应温度40℃,反应时间6h时,产物环氧值为0.291eq/100g,产率95.4%,黏度为1180mPa·s。通过FTIR和1H NMR对产物结构进行表征,并将不同质量分数的DEEBAPO掺入到E-51环氧树脂中,与二乙烯三胺(DETA)进行固化,并对其固化物力学性能进行测试。因为DGEPBA的掺入,使得E-51固化物在抗拉伸、抗冲击方面均有明显提高。热失重(TGA)分析表明固化物热稳定性稍有提高,扫描电镜(SEM)显示断裂面为韧性断裂。 相似文献