The Preparation And Modification Of SF/PCL Fibrous Membrane

[Objectives] PCL, a biomedical material and biodegradable material, becomes one of the important research direction in the field of biodegradable materials in recent years. In this project, the poly caprolactone and degumming processing natural silk were taken as raw materials, through the electrostatic spinning technology preparing the poly caprolactone silk fibroin membrane and through different catalytic systems, caprolactone being modified in the blended membrane, prompting them to again ring opening polymerization to form long chain structure, and exploring the different catalytic system for poly caprolactone modification, in order to select suitable method to improve the blended membrane mechanical properties, for the construction of poly caprolactone silk fibroin scaffold providing experimental basis, expanding the material source of tissue engineering.[Methods] First of all, using the electrostatic spinning process for the preparation of poly caprolactone electrospinning silk fibroin blended liquid, and then using scanning electron microscope (SEM) to observe the fiber morphology and diameter distribution, to determine the best blended membrane, the blended membrane after processing was placed in stannous caprylate catalytic initiator system to observe the blended membrane modification of change, and to explore the change of blended membrane structure and mechanical properties after stannous caprylate catalytic initiator system’s processing.Then, the modified blended membrane is placed on gamma ray radiation field with changing the irradiation conditions and irradiation environment on poly caprolactone silk fibroin blend membrane being modified, by scanning electron microscope (SEM), gel permeation chromatography (GPC) on modified blend membrane being characterized, comparing different irradiation treatment on poly caprolactone electric spun silk fibroin membrane modification effect.[Results](1) In order to ensure good biocompatibility of silk fibroin, the integrated use of high molecular weight water soluble polymer dialysis and high-voltage electrostatic spinning technology, successfully used six fluorine isopropyl alcohol as the solvent of silk fibroin solution poly caprolactone blended membrane is prepared.(2) The conditions of different temperature of stannous caprylate catalytic system exploration on the ring opening polymerization,40℃-170 ℃ temperature range in all can cause poly caprolactone ring opening and re-polymerization, forming a new polymer. New polymer number average molecular weight increases with the increase of temperature, blended membrane in stannous caprylate catalytic system product conversion rate increases with temperature rise.(3) The best temperature parameters:stannous caprylate catalytic systems cause poly caprolactone electric spun silk fibroin membrane ring opening polymerization modification temperature is 80 ℃, obtained blended membrane, appearance neat, space structure, good toughness and mechanical properties of the best.(4) Treated with stannous caprylate catalytic system blended membrane degradation speed slowed considerably, and a controllable degradation speed, can meet the demand of tissue regeneration technique.(5) By gamma ray irradiation treatment can obtain re-crosslinking poly caprolactone silk, silk fibroin electrospinning of poly caprolactone membrane mechanical properties are part of the reinforcement, and with the increase of molecular weight poly caprolactone, blended membrane increases radiation crosslinking advantage, its mechanical modification is obvious. Compared with irradiation temperature, vacuum degree, the irradiation dose of blended membrane radiation crosslinking modification is more significant.(6) After gamma irradiation crosslinking treated, blended membrane degradation of performance is improved obviously. In a certain range, with the increase of irradiation dose, degradation rate is slowing.(7) Stannous caprylate catalytic system and gamma rays can realize poly caprolactone electric spun silk fibroin membrane modification, is a kind of effective way to improve blended membrane degradation performance and mechanical properties.[Conclusions] In this topic, by high voltage electrostatic spinning technology, three-dimensional structure of poly caprolactone silk fibroin fiber membrane was successfully prepared, using ligand complex catalytic systems cause blended membrane of poly caprolactone ring opening polymerization chain extension reaction, and forming long-chain structure of polymer, thus to improve the blended membrane mechanical properties and performance. At the same time, application of gamma ray irradiation to electrospinning membrane modification research, explore different irradiation treatment on polcaprolactone electric spun silk fibroin membrane performance impact, finally get good spatial structure, mechanical properties and degradation rate of blended membrane, for tissue engineering scaffold and tissue regeneration technology providing a new way.