中文摘要：

采用熔融扩链法制备了高分子量的全生物基聚丁二酸丁二醇酯（PBS）-聚丁二酸异山梨醇酯嵌段共聚酯.GPC测试结果表明,该嵌段共聚酯在较高的异山梨醇（Is）含量时仍具有较高的分子量,其M_n介于3.5×10^4-7.0×10^4之间.采用TGA和DSC对嵌段共聚酯的热稳定性和结晶性能进行了研究,结果表明嵌段共聚酯保持了PBS优异的热稳定性和结晶性能,即使异山梨醇含量达60 mol%,其熔点较PBS仅下降2 K.采用DMA分析了嵌段共聚酯的玻璃化转变温度Tg,发现随着异山梨醇含量的增加,其T_g随之升高,当Is含量为60mol%时,嵌段共聚酯的Tg高达68℃,并且共聚酯的2个链段具有很好的相容性.力学性能测试结果表明,异山梨醇的引入可使PBS的力学性能得到明显地提高和调控,随着异山梨醇含量的增加,嵌段共聚酯的拉伸强度先增加后降低,断裂伸长率约是PBS的2倍,其中,当异山梨醇含量达60 mol%时,嵌段共聚酯的屈服强度由PBS的35.0 MPa增至43.0 MPa.

英文摘要：

In order to obtain copolyesters containing sugar-units with high meling point and crystallization ability,poly（ butylene succinate-isosorbide succinate） multiblock copolyesters（ PBIS） were successfully synthesized by chain-extension of the dihydroxyl terminated prepolymers. GPC results showed that high molecular weight PBS-based copolyesters with high content of isosorbide were easily obtained through chainextension. Their M_n values were in the range of 35000- 70000. TGA and DSC results indicated that the PBISx multiblock copolyesters still maintained the good thermal stability and crystallization ability. When the content of isosorbide was up to 60 mol%,the T_m of copolyesters only declined 2 K compared with that of PBS. The effect of composition on the miscibility of PBS and PIS segments in PBISx multiblock copolyesters was studied by DMA. The results indicated that the miscibility of PBS and PIS segments in PBISx multiblock copolyesters changed from miscible to partially miscible,and finally changed to miscible with increasing isosorbide content.And the Tg values of copolyester increased with the increase of Is content,in which the Tgof PB45I34S60 was as high as 68 ℃. The mechanical properties of PBS were improved and controlled by adjusting the content of isosorbide. The tensile strength of PBISx firstly increased and then decreased,and their elongation at break was double that of pure PBS. When the content of isosorbide was 60 mol%,its tensile yield increased from 35. 0MPa of PB45 S to 43. 0 MPa.