由氧化苯乙烯制备聚单硫代碳酸苯乙烯酯【字数:10352】
同时也未检测到碳酸酯链节、二硫代碳酸脂链节或相应的环状产物,这表明氧硫交换反应得到完全抑制,但因有STO单体均聚有聚醚生成导致无法得到全交替结构共聚物。共聚物上单硫代碳酸酯链节比例最高为88%。
目录
Abstract
Carbonyl sulfide (COS) is a monocarbon (C1) monomer with similar structure to carbon dioxide (CO2) and carbon disulfide (CS2), which has been regarded as a catalyst poison and industrial waste gas and mainly used as a soil fumigant. The mainstream research direction is around how to deal with COS, and the application of COS research is very limited.
The DMCC catalyst is a typical coordination complex in terms of structure, called the double metal cyanide complex.It was first used to catalyze the ringopening polymerization of epoxides to prepare polyether polyols. It can effectively catalyze the ringopening polymerization of epoxides. The structure of ZnCo (III) DMCC is similar to Prussian blue structure, and the crystal cells are planecentered cubic lattice structure, with high crystallinity.
The catalytic copolymerization of Carbonyl sulfide (COS) with styrene oxid(STO)was studied. Taking COS as a single carbon monomer, it was polymerized with styrene oxide ring opening under the action of ZnCo (III) DMCC catalyst, and poly(thiocarbonate) with high conversion rate, high product selectivity and high polymer linkage selectivity was synthesized
DMCC can effectively catalyze COS copolymerization with styrene oxide. The conversion rate was greater than 99% and the product selectivity was greater than 95%. Add too much COS, under the condition of 80 ℃ to 110 ℃ higher catalytic activity and selectivity, in its crude product hydrogen nuclear magnetic ring byproducts was detected in the spectrum. At the same time,no carbonate linkage joints, dithiocarbonate linkage joints or corresponding ring products were detected, which indicated that the oxygensulfur exchange reaction was completely inhibited. However, due to the formation of polyether by STO homopolymerize,it was impossible to obtain fully alternating structure copolymers. The highest proportion of poly(thiocarbonate) linkage on the copolymer was 88%.
Key Words:Carbonyl sulfide;ZnCo(III)DMCC;product selectivity;linkage selectivity
第一章 绪论1.1 氧硫化碳
1.1.1氧硫化碳的性质
[1]氧硫化碳(COS),又称羰基硫,英文名称 carbonyl sulfide。常温常压下纯净的氧硫化碳是无色无味气体,可是通常因为其含有少量硫化氢而带有鸡蛋发臭的气味。氧硫化碳微溶于水,溶于乙醇和甲苯。极易溶于二硫化碳和氢氧化钾溶液。氧硫化碳可燃并且有毒,并且对人们的喉咙、肺部、皮肤、眼睛、鼻子等器官都有不同程度的刺激和腐蚀。
从氧硫化碳的分子构成来看,可以视为是CS2分子中的一个硫原子被氧原子取代也可以看做CO2分子中的一个氧原子被硫原子取代,物理性质大多介于二氧化碳和二硫化碳间,然而结构上的不同则导致了三者化学性质的区别,相比于两者,氧硫化碳具有更高的反应活性,能够和众多化合物发生反应。氧硫化碳、二氧化碳、二硫化碳三者都是线性结构,然而二氧化碳和二硫化碳为对称结构,其偶极矩为零,但氧硫化碳因为硫原子和氧原子的不同而具有偶极矩,并且碳氧键的键能与键长与碳硫键也不尽相同。由于这种特殊的非对称结构,在发生化学键断裂时随着C=S键和C=O键的断裂会产生两种不同的结构,因此使氧硫化碳比起另外两者在参与化学反应时会发生更多的变化情况。
表1.1 COS,CO2,CS2部分物理化学性质
性能
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