The Preparation And Performance Study Of Modified Pcl/sf Electrospinning Fiber Membrane

Objectives:This experiment was to prepare PCL/SF electrospinning fiber membrane with PCL and regenerated silk fibroin,according to the chemical characteristics of PCL and SF,alcohol-water system and stannous caprylate catalytic reaction were used to modify the fiber membrane,and the impacts of alcohol-water processing system and the conditions of different catalytic reaction on the structure and performance of PCL/SF electrospinning fiber membrane were observed,in order to improve the performance of electrospinning fiber membrane and provide the experimental basis for expanding the applications in the field of tissue engineering.Methods:PCL/SF(3:7)were prepared by high voltage electrostatic spinning technology with a certain spinning process parameters.Firstly,modified electrospinning membrane by ethanol-water soak,and divided into two groups:the first group was soaked after the stretch and the other group was stretched after soaking.The change of the fibre diameter and morphology structure of the fiber membrane were observed by SEM,and the character of the membrane's structure and properties were analyzed by the Fourier transform infrared spectrum(FTIR),X-ray diffraction analysis,mechanical property testing and surface wettability test.Then,the membranes were modified by using stannous caprylate as the catalyst under varied reaction time and temperature of polymerization.The ideal modification conditions were determined by the fiber morphology and structure under SEM,characterized the structure and properties of electrospinning film after copolymerization modification and ethanol treatment,and were analyzed and compared.Results:1.By high voltage electrostatic spinning technology,with six fluorine isopropyl alcohol as organic solvent,the PCL/SF(3:7)electrospinning fiber membrane were prepared successfully.2.After the ethanol-water solution post-processing,the fiber diameter of the soak first then stretch group was increased from 710±247nm to 1206±471nm,the surface of the fiber group was cracked,and in the group of first stretch then soak,the fiber diameter of the membrane was enlarged to 2088±1006nm with smooth surface without cracks.The results of further mechanical properties showed that the tensile strength of the film after ethanol treatment was higher than that of the untreated membrane(P<0.05).The results of the film surface wettability showed that the static contact angle of the untreated membrane was reduced from 117.07±7.18° to 39.20 ±5.90 °,and the difference was statistically significant(P<0.05).3.Under the condition of different reaction temperature and reaction time,it could be found that when polymerization temperature was from 50? to 80?,reaction time was in the scope of 0.5h to 4h,ring opening polymerization reaction could occur.With the increase of copolymerization modification polymerization temperature and reaction time,more new polymer generated on the fiber surface.When reaction time was 2h or above,fiber begun to fuse.4.The ideal reaction temperature was 70?,and the reaction time was 1h.Under this reaction condition,the fiber surface appeared a large number of beaded structure with uniform distribution and the space structure was regular with certain pore.The crystallinity was increased after modification,the tensile strength of the modified membrane was higher than that of the original membrane,and the difference was statistically significant(P<0.05).The results of hydrophilic test showed that the static contact angle decreased from 117.07±7.180 to 51.30±8.02° after the modified treatment,and the difference between the original membrane and the modified membrane was statistically significant(P<0.05).Conclusions:Using alcohol-water system could affect the SF conformation and the stannous caprylate catalytic systems could promote the ring of PCL opening and polymerization again.In this project,PCL/SF electrospinning fiber membrane were dealt by two ways.After the modification,fiber membrane structure changed.The crystallinity,mechanical properties and hydrophilia were enhanced.These two methods both were effective ways to improve electrospinning film properties,but ethanol-water post-processing way was better.