Studies On The Preparation And Performancr Of Antimicrobial/Anticoagulant Silicone Rubber

Polymer materials have already been widely used in medical devices and artificial organs and polymer materials Has a pivotal role in the biomedical field. When the polymer medical products contacted with living tissue, will produce some negative effects, such as the formation of thrombus. In addition, in the hospital environment, medical staff is hard to avoid carrying bacteria.The bacteria may cause infections,there were nearly one hundred thousand people die each year from such infections in the United States.Therefore, the antimicrobial properties of the materials is especially important.This article selects the methyl vinyl silicone rubber as matrix material.The hydroxypropyl chitosan(HPCTS), montmorillonite,Titanium dioxide(TiO2),Chlorhexidine acetate(CA) modified silicone rubber was prepared by mechanical mixing method. The antibacterial properties and the mechanical properties of the modified silicone rubber were Studied. Using hydroxyl ethyl methacrylate (HEMA) and N-vinyl pyrrolidone (NVP) as raw materials for the modification, the modification methods included surface grafting and Semi-Interpenetrating Polymer Network(Semi-IPN).Different testing methods were used,such as SEM,TEM,DSC,IR, XPS,static water contact Angle,the sterilizing rate test,the PT test. SEM and TEM observation found that organic montmorillonite,CA,HPCTS, TiO2,HEMA modifier evenly dispersed in the silicone rubber and the modifier had good compatibility with rubber matrix. SEM also found that PVP and PHEMA grafted on the surface of the rubber forming membrane.But the membrance was irregularity.Static water contact Angle test showed that the hydrophilic of rubber was significant improved after grafted PVP and PHEMA layer.Sterilizing test showed that the sterilizing rate was significant improved by using organic montmorillonite,CA,HPCTS,TiO2.The sterilizing rate of CA and HPCTS could reach100%,which were better than organic montmorillonite and TiO2. The PT of CA could reach60.8s, which were better than others.Surface grafted hydrophilic materials could also show good anticoagulant capability.