ε-己内酯与L-丙交酯共聚物的合成及其电纺丝加工初步研究

SYNTHESIS OF COPOLYMERS OF ε-CAPROLACTONE AND L-LACTIDE AND A PRELIMINARY STUDY ON THEIR ELECTROSPINNING PROCESS

采用辛酸亚锡为催化剂,1,4-丁二醇为引发剂,制备了不同组成、不同分子量的ε-己内酯/L-丙交酯共聚物,并用GPC、FTIR、1H-NMR、DSC和XRD等分析方法表征了该共聚物的结构.结果表明通过改变初始投料中两单体的比例,可以调节共聚酯的分子结构;调节单体与引发剂的比例,可以调节共聚酯分子量,进而影响到其形态与性质.采用高分子量的共聚物进行电纺丝加工,得到了微米级超细纤维无纺布,由SEM可观察到纤维之间有不同程度的粘结.在孔隙率约为75%左右的情况下,该无纺布的抗拉强度可达6.1MPa,延伸率为500%.

A kind of ε-caprolactone/L-lactide copolymers with varying compositions and molecular weights has been synthesized by using Sn（Ⅱ）octoate as catalyst and 1,4-butanediol as initiator.The copolymerization was carried out under vacuum at 130℃ for 24 h.The copolymer structure was characterized in detail by using GPC,FTIR, ^1H-NMR,DSC and XRD analyses.It was shown that the chemical compositions and molecular weights of the copolymers were adjustable by changing the monomer molar ratios in feed,and their appearances and physical characteristics were closely related with the variation of composition and molecular weight.The number average molecular weight is changed from 1×10^4 to 1×10^5. The melting temperature is in a range from 15℃ to 55℃.A preliminary study was also conducted on the electrospinning process of the resulting copolymers.The copolymer was first dissolved in CH2Cl2 at a concentration of 6 wt%.The solution was then delivered at a constant flow rate （5 mL/h） with an air gap of 20 cm between the metal collector and the needle tip at a driving voltage of 20 kV.Finally ultrafine fibers were obtained,and melting binding between different fibers was evidenced by SEM observation.The solvent cast membrane of LC-96-6k was found to be stronger than that of LC-50-6k.However,their electrospinning nonwoven fabrics showed lower but comparable mechanical properties.