Study On The Hydrophilic Modification Of Polyethylene Wax And It's Emulsification

Polyethylene wax,a kind of polyolefin with low molecular weight,are widely used in industrial fields because its advantages of non-toxic,tasteless,non-corrosive,stable chemical property,good wear resistance,high hardness and so on.PEW is not easy to use as it exists as solid at room temperature.For easy to use,PEW is used in the form of emulsion.Because PEW is nonpolarity polymer and insoluble in water,it cannot be directly emulsified with water.Usually,it can be emulsification under the condition of add emulsifier and stirring with external force.But the method needs 15-20% of weight of PEW to be added.The emulsion of PEW is usually expensive due to the price of emulsifier is much higher than polyethylene wax.Additionally,the stability of emulsion of PEW prepared by the mention-above method is poor and easy.These defects led to the application of PEW are limited.In view of the deficiencies of craft process and the storage and transportation process of the current problems.The feasibility preparing the self-emulsifying polyethylene wax by saponifing the polyethylene wax grafting maleic anhydride copolymer(PEW-g-MAH)is investigate in this work.the relationship between self-emulsifying ability and grafting ratio of saponification products,the effects of process conditions of PEW-g-MAH copolymer on properties of emulsion were studied.The process conditions of synthetic self-emulsified polyethylene wax were determined and the following conclusion were drawn:(1)The self-emulsified polyethylene wax can was prepared by saponifing the polyethylene wax grafting maleic anhydride copolymer.The saponified PEW-g-MAH can form emulsion by means of self-emulsion as its grafting ratio more than 3.94%.The self-emulsifying ability of saponified PEW-g-MAH copolymer increase with the increasing grafting ratio of PEW-g-MAH copolymer.When its grafting ratio more than 6.58%,the saponified PEW-g-MAH can form emulsion with good dispersity,distribution uniform and storage stability.(2)The soild content and emulsifying temperature are the main factors affectting self-emulsifying ability and the properties of emulsion.When solid content was 30~40%and emulsifying temperature was 125~130°C,The saponified PEW-g-MAH copolymer can form emulsion with good dispersity,distribution uniform and storage stability.(3)The optimum emulsifying condition for PEW-g-MAH graft copolymer were as follow: solid content was 40%,emulsifying temperature was 130°C,emulsifying time was30 min,and shear rate was 5000 r/min.under above condition,the prepared emulsion withexcellent good dispersion,long-term stability and distribution uniform and minimum size of 1.88 ? m under this condition.(4)The type of saponification has great influence on the self-emulsifying ability and properties of emulsion of saponified PEW-g-MAH copolymer.The self-emulsifying ability and the properties of emulsion of saponification PEW-g-MAH copolymer,obtained by the reaction of PEW-g-MAH graft copolymer with NaOH that the self-emulsifying ability and the properties of prepared emulsion,is best.