用^(1)H NMR方法研究聚砜-聚脂类嵌段共聚物的组成和序列分布

The Determination of Composition and Sequence Distribution in Polysulfone-Polyesters Block Copolymers by^(1)H NMR

本文测定了一系列聚矾-聚酯嵌段共聚物的高分辨核磁共振谱,研究了共聚物的组成和序列分布,由^(1)H NMR谱图的峰面积算出了共聚物的无规度(B)及数均序列长度(L),B值均在O<B<1范围内又一次证明共聚物系嵌段共聚物,其结构是由聚酯链段封端的多嵌段结构,研究结果还表明:反应条件、加碱量及加碱时间、加料方式等对B均有影响,尤以加料方式影响极大,B值还与起始的投料比及二元醇的结构有关。

High resolution NMR spectra of several kinds of Polysulfone-Polyesters(PSF-PPT, PSF-PBT, PSF-PHT, PSF-PDET, PSF-PTET) block copolymers were measured.The composition and sequence distribution of Polysulfone-Polyesters block copolymers were studied. Proton signals due to helerolinkages could be observed in these block copolymers, and the average sequence length (L) and the degree of Randomness (B) in the Polysulfone-Polyesters block copolymers were calculated from the intensities of their signals.B of block copolymers lie in the region of 0<B<1.The structure of Polysulfone-Polyesters block copolymers is shown as below.It was shown that the degree of randomness (B) and the average block length (L) in block copolymers. were relatively dependent on the reaction conditions, mixing sequence of the reactants, various feed ratios and structure of diols.