支链含氟聚酯的合成和性能

Synthesis of Branched Fluorine-containing Polyesters and their Properties

用1H,1H,2H,2H-全氟-1-癸醇对1,2,4-苯三酸酐中的一个官能团进行封端后替代部分顺丁烯二酸酐,与新戊二醇共缩聚合成了支链含氟聚酯,然后在含氟聚酯中加入交联剂进行固化反应制备出支链含氟聚酯膜。使用红外光谱、XRD、GPC、TG和DSC等手段表征含氟聚酯的结构、分子量和热稳定性,用万能试验机、接触角测试仪和X射线电子能谱分析了含氟聚酯膜的力学性能、表面性能及表面元素含量。结果表明,在聚酯中成功引入含氟基团使含氟聚酯比无氟聚酯的分子量增大,热稳定性先提高后降低,初始分解温度最高达299.41℃,玻璃化转变温度由6.24℃提高到46.65℃;随着含氟基团含量的提高聚酯膜的断裂伸长率降低而拉伸强度提高,拉伸强度最高达到19.97 MPa;含氟基团由含氟聚酯膜的本体向表面迁移,随着含氟基团含量的提高聚酯膜的水接触角和油接触角逐渐增大,使聚酯膜具有疏水性。

The polyester containing fluorine in its branch chains was synthesized.First of all,one of the functional groups of 1,2,4-phthalic anhydride was capped using 1H,1H,2H,2H-perfluoro-1-decanol,then a part of the pentabutyl diacinate was replaced by terminated 1,2,4-phthalic anhydride to obtain fluorinated polyester with neopentyl glycol via copolycondensation reaction.After that,films of the fluorinated polyester were prepared by curing with the crosslinker.The structure,molecular weight and thermal stability of fluorinated polyester were characterized by means of IR,XRD,GPC,TG and DSC.The mechanical properties,surface properties and surface element content of fluorinated polyester films were assessed by using universal testing machine,contact angle tester and X-ray electron spectroscopy.The results show that with the increase of the functional groups,the molecular mass of fluorinated polyester increased compared with the non-fluorinated polyester,while the thermal stability of fluorinated polyester increased firstly and then decreased;The maximum initial decomposition temperature is as high as 299.41℃;The glass transition temperature was gradually increased from 6.24℃to 46.65℃;the elongation at break of fluorinated polyester film decreased while the tensile strength increased gradually,and the maximum tensile strength reached 19.97 MPa.The fluorinated groups migrated from the main body to the surface of the fluorinated polyester film.Furthermore,the water contact angles and the oil contact angles of films increased with the increase of fluorinated groups while the films gained hydrophobicity.