Study On Acrylate Emulsion Adhesive Used For Polyolefins

With the features of abroad source and widely adhesivity,the acrylic emulsion adhesives show better color phase,good heat resistance and good weather resistance while bonding polyole substrate, low cost,environmentally benign .So recently,this field become a hot innoversion and be paid attention to by more and more learner.In this dissertation, redox intionator are used to synthesize three kinds acrylic emulsion adhesives: one is blending tackifier and acrylic emulsion.the others are adding modificated monomer colonphony and organic siloxane to acrylic polymerization.On the base of blening tackifier and acrylic emulsion ,a series of acrylic emulsion adhesives had been prepared by changing polymerization methods ,the time of dip ,the temperature of polymerization,the amount of initiator,the ratio and the amount of emulsifier,content of comonomers,kind and amount of wetter ,amount of tackifier.Adhesion properties were tested as well as emulsion properties such as viscosity of latex and average size of latex particles etc.On the base of copolymerization ,a series of acrylic emulsion adhesives had been prepared by changing the kind and content of tackifier ,kind of solvent , the amount of organo siloxane.Adhesion properties were tested as well as the mentioned methods.The experiment showed : (1) Polymerization method had an important effect on properties of acrylic emulsion adhesives,and seed-polymerization was proved referable. (2) The systematic properties reached preferable level at the optimized reaction conditions: reaction time 4 hour, polymerization temperature 50℃ and stiring speed 80r.min^-1;(3)Influence of monomer to emulsion copolymerization. Crylic acid shows preferable capability among several functional monomers,and the rate of coacervation falling and systemic stability with increase of it, The peeling strength attained 0.27 kN.m^-1 when amount of crylic acid 6% as soft and hard monomer ratio of 2:1.(4)In the additive of polymeric emulsion. The proper range of redox initiator was about 0.3% 0.8%;amount of buffer 0.4⁰.6g,amount of emulsier 3%;Wetter of LSR101 show better adhesional wetting than other two wetters intermingling with polymezation.With increase of wetter of LSR101,contact angle show obvious downtrend and keep 25°invariable.Amount of wetter 0.9%,peeling strength curve showed a peak at 0.28 kN.m^-1 .The contact angle gradually decrease with increase of tackifier,and the adhesive enhance firstly then decrease, The peeling strength of adhesive is improved to 0.33 kN.m^-1 with the amount of tackifier 25%.Infrared spectroscopic analysis(IR) and differential scanning calorimeter(DSC) are used to study the modified copolymerization emulsion with colophony and withorgano siloxane fisterly.The results showed copolymerization occured .At the same time, experiment showed:hydrogen colophony exhibite good performance modification. Polyethylene films were tore partly and entirely in the peeling strength tests when the parts of hydrogen colophon reached 10g,the high peeling strength gained 0.56 kNm"',then decreased and the amount over 25g they cannot copolymerze and bring phase separating. A small quantity of organo siloxane may enhance the peeling strength of adhesive little,but peeling strength of adhesive will decline sharply with amount of it increase even they cannot compare with pure crylic emulsion adhesive,so the amount of organo siloxane go beyond of limit of 7% as modified comonomers.At the same time ,we found absorbency of adhesive decline with weight enhancing and exhibit good water-resistant.when the weight of organo siloxane reach 15% ,they can be used as water-resistant coating for they can not blanch while immerseing in water when absolute torrefaction.