Study On The Graft Modification Of Chlorinated Polypropylene

Due to good integrate properties and special ratio of its properties to price, polypropylene(PP) has gained great development in the production and application. It was widely used in the field of film, fibre and plastic products. With the increasing demand for performance, people want the more excellent surface property and the more beautiful appearance. Because of low surface tension, lack of chemical functionalities and high crystallinnity, it is difficult to be adhered for PP. However, chlorinated isotactic polypropylene(CIPP) has good adhesion properties to PP, but, the adhesion force is low when CIPP is used as primer of PP/coat. So this paper presents the study of acrylates grafting CIPP.The pilot study was made to synthesize the acrylates/CIPP compound, the results revealed that graft percent was low only with BA, MMA, AA, VAC or AN as graft monomers. However, the results was very ideal when AM was added in reaction system on the basis of BA, MMA and AA as graft monomers. With Solution polymerization as synthesis method and with graft percent as index, the influencing factors and their influencing regularites were researched, from which the best graft process was researched using orthogonal experiments. Then the graft method of dropping monomers was compared with integrating monomers under the conditions of the best graft process.The mechanism of graft polymerization was researched with IR and DSC as token methods. By ESCA test, atoms and its concentration was analized on five different surface and the mechanism of CIPP-g-acrylates improving the adhesion force of PP/coat were studied.In this paper, BA, MMA, AA and AM were succeeded in being grafted on the CIPP chains by solution polymerization. In the best graft process, the graft percent was 14.9% and the adhesion force was 100%, which can satisfy the demand of use. By being compared with CIPP, the rheological property and themoability of CIPP-g-acrylates were improved obviously. For adhesion property, environment, baking tempreture and graft process parameters have great influence on it.