Study On The ACR Modification For PVC And ACR Particle Diamantes Controlled By Agglomeration

The acrylate copolymers (ACR) with core-shell structure were synthesized by seed emulsion polymerization with butyl acrylate and 2-ethylhexyl acrylate as core comonomers, with ethyl acrylate and methyl methacrylate as shell comonomers.The emulsoid particle size and its distribution were determined by dynamic laser scattering and TEM. The core-shell structure was observed by TEM. The results indicated that the emulsoid particles have obviously core-shell structure; its diameters are between 100 to 160nm. The glass-transition temperatures were measured by DSC, the results showed that there are three glass-transition temperatures in ACR.The properties of PVC/ACR blends, such as notched impact strength, tensile strength were determined. TEM was employed to examine the dispersion state and the fractured surfaces of PVC/ACR blends. The effects of the amount of emulsifying agent, initiator and crosslinking agent, ratio between core and shell, monomer composition, solid content of emulsion, polymerization temperature, the amount of ACR in PVC/ACR blends on mechanical properties were discussed.Beside, the reversibility of agglomerating peaks is studied. The first agglomerating peak is incomplete un-reversible and the second agglomerating peak is reversible.We discovered that in the agglomerating peaks is move back vvh^n content of AA in agglomeration latexes is increase. But the reason of the increase of the second agglomeratingpeak is the reciprocity of volume restriction effect and the bridging effect.We proved that the excessive emulsification minish the particle diamante in agglomerating peaks, and make the R (B/A) become larger.In the last, we find latexes (A)'s effection is small.