A Synthesis And Characterization Study Of Weathering And Transparent MBS For PVC Impact Modifier

MBS(Methylmethacrylate-Butadiene-Styrene) resin is a new type of synthetic polymer materials which are composed of three basic components, butadiene(B) styrene(S) and methyl methacrylate(M) in the concept of particle design.It is used to be the impact modifier of PVC.But the traditional MBS resin contain unsaturated double bond in the rubber phase,under the conditions of heat or Light,it will be aged and performances will decline,so it isn't suitable for outdoor applications.This paper basises the transparent mechanism and mechanism of impact resistance of MBS resin,seed emulsion and submicroscopic particles design are adopt.PVC transparency impact modifier MBS with a good weather resistance was synthesized by adding new components butyl acrylate and regulating the proportion of each component in the MBS resin formula.A multi-step process of seeded emulsion polymerization was adopted so that the resin has a typical core/shell structure.Particle center is a rubber core with low elastic modulu,and outer layer is a graft-shell formed of Methylmethacrylate and Styrene with high elastic modulu.The shell layer and the PVC resin has good compatibility.MBS can be uniformly dispersed in the PVC matrix,so PVC/MBS mixture form "an island structure" and this island structure give a full play role as a MBS impact modifier.The key factors to prepare the MBS resins such as butyl acrylate content, rubber-phase particle size,proportion of grafted layer,as well as the conditions of systematic preparation were investigated.A reasonable polymerization formulation and technological conditions were determined.MBS was melted into PVC,by a mixer.The micro-structure of th MBS and MBS/PVC plasticizing system were analysised and the mechanical properties, flow Behavior change,optical performance and thermal properties of materials were studied..The results showed that the prepared MBS resins have a good impact resistance,transparency and weather resistance.It can be used as the transparency impact modifier of PVC resin.