Comb-Like Polymers with Rigid Main-Chain and Their Crystallization

为了研究该项目，合成了4种具有长烷基侧链的梳状聚合物，并用DSC方法测定了侧链结晶的程度：1)交替的苯乙烯-丙烯酸酯共聚物，其中甲基在两个单体单元的α位置被累积取代：累积取代的甲基和苯乙烯单元中的苯基使共聚主链变得更加刚性，并抑制了侧链的结晶程度。2)由2-烷基三亚甲基二醇和脂肪族二元酸组成的聚酯：二元酸到二十二酸，因此在15，19，23，23，15，19，23，23，15，19，23，23，15，19，23，23上出现烷齿的梳状聚合物对26个主链原子进行了研究，在这种柔性的聚酯型梳状聚合物中，尽管侧链的齿间距很宽，但很容易发生结晶。主链亚甲基也参与了结晶反应。3)聚乙炔：以1-烯烃为原料，在钨、钼催化剂作用下合成了高相对分子质量的聚乙炔。4)2-烷基三亚甲基二胺和脂肪族二酸聚酰胺：酰胺键中C-N的双键特性使主链刚性，侧链结晶程度小于相应的聚酯梳状聚合物。综上所述，各种梳状聚合物的侧链结晶受到主链刚性(或柔性)的影响，符合我们的结晶梳状聚合物的结构模型。

To investigate the titled project, 4 types of comb-like polymers with long alkyl side chains were synthesized and the extent of the side-chain crystallization was determined by DSC method.1) Alternating styrene-alkyl acrylate copolymers, in which methyl groups were cumulatively substituted at the alpha-positions of both monomer units: Cumulatively substituted methyl groups and the phenyl group in the styrene unit made the copolymer main-chain increasingly rigid and suppressed the extent of crystallization of the side-chain.2) Polyesters from 2-alkyltrimethylene glycols and aliphatic diacids: Diacids up to henicosanedioic acid, and therefore comb-like polymers with the alkyl teeth appearing on every 15, 19, 23, 26 main-chain atoms were studied.In such flexible polyester type comb-like polymers, side chain crystallization occurred easily in spite of their wide teeth spaces. The main-chain methylenes were also participated in the crystallization.3) Polyacetylenes: High molecular weight polyacetylenes were obtained from 1-alkynes by using W and Mo catalysts. The rigid main-chain of polyacetylenes due to their carbon-carbon double bonds suppressed the side-chain crystallization when compared to the corresponding polyolefins.4) Polyamides from 2-alkyltrimethylene diamines and aliphatic diacids: The double bond character of C-N in the amide linkage made the main-chain rigid and the extent of side-chain crystallization was smaller than the corresponding polyester comb-like polymers.In summary, it was shown that the side-chain crystallization of various comb-like polymers was influenced by the rigidness (or flexibility) of the polymer main-chain in accordance with our structural model of crystallized comb-like polymers.