Preparation And Characterization Of Modified Silicone Rubber Composite

The main chain of the silicone rubber is composed of silicon and oxygen atoms and the silicon atoms with different side groups.So it has a lot of excellent properties,such as high and low temperature resistance,electrical insulation and air permeability,avirulent insipidity,etc.Therefore silicone rubber has a very wide application in the aerospace,automotive electronics,medical equipment and other fields.But with the development of high and new technology,the defect of silicone rubber is becoming more and more obvious,such as,poor mechanical properties,poor oil resistance,poor hydrophilicity and poor bonding performance with other materials.To sum up,the modification of silicone rubber is imperative.In addition to the physical and chemical modification methods,silicone rubber nanocomposites is also an important means of the preparation of high performance silicon rubber.First of all,we synthesized polysiloxane with different vinyl content(5%?10%?20%?30%?40%)by anionic ring-opening polymerization and then conducting modification on the basis of the silicone rubber.First of all,grating mercapto propionic acid on the side chain of silicone rubber through click chemistry which is bulk modification.Controlling mercapto propionic acid with double bond ratio was 1.5:1 and the conversion rate could reach 100%.Results show that when the side chain content was more than 10%,there was no obvious crystallization.And the glass transition temperature had varying degrees(4?-43?)with the increase of side chain content.Moreover,the water contact angle was reduced to 60?.Preparing silica/modified silicone rubber composites.Result showed that the introduction of the mercapto propionic acid can enhance the interaction between silica and silicone rubber,Payne effect is decreased obviously.We conducted surface modification on vulcanized silicone rubber with different vinyl content,grafting with mercapto propionic acid and hyaluronic acid.Water contact angle reduced from 110° to 40°,and the hydrophilic keep well within a week,at the same time guarantee the no cytotoxicity in vitro.The second part of this subject we prepared the graphene oxide and epoxy silicone rubber respectively.And then prepared GO/ESiR composites by solution compounding method.The results show that the graphene oxide was successfully dispersed as few layers even a single layer,monolayer dispersion.And the movement of molecular chain was limit due to GO,so that the glass transition temperature increased by about 4?.The tensile strength was increased about 1.5 times when the GO content reached 1wt%.