The Preparation Of Narrow Distribution Of Mono Epoxy Polysiloxane Emulsion Particles And The Reation Kinetics Between Mono Epoxy Polysiloxane Emulsion Particles And Gelatin

Mono epoxy terminated polydimethylsiloxane（PDMS-E）is a polymer with strong hydrophobic,super flexible and low surface energy.Grafted onto gelatin with the excellent film forming property and filling property to prepare new materials with high performance.PDMS-E graft gelatin reaction is a heterogeneous reaction.Emulsifying PDMS-E,reducing the interfacial tension,is the direct way to promote heterogeneous reaction.The purpose of this study is the reaction of PDMS-E graft gelatin and the reaction kinetics.So determine the suitable reaction conditions for expanding the scope of the modified material application.Latex particle size affects the surface structure,and then affects the chemical reaction on the surface of latex particles.In this paper,firstly PDMS-E latex particles with narrow distribution were prepared by reversed phase emulsion-ultrasound method.By investigating and analysing the effect of the preparation conditions on particle size and size distribution,determinated the optimization conditions:[3-（2,3-epoxy-propoxy）propyl]-w-butyl-polydimethy siloxanes（PDMS-E,M_W=999）:sodium dodecyl benzene sulfonate（SDBS）:sodium dodecyl sulfate（SDS）:cetyl alcohol（CA）=1:0.731:0.3507:0.845（mol:mol:mol:mol）,pH 3.75,water dropping speed 31.25μL·min^-1.Ultrasonic optimization parameters:power 100 W,time 2.5 min,temperture 2℃.PDI:0.104～0.450.The effect of ratio,latex particle size,reaction temperature,gelatin concentration,pH and reaction time on the reaction of PDMS-E graft gelatin were investigated.Primary amine conversion rate was determined by Van Slyke method.Determinated the optimization conditions:gelatin water（5%,w/w）,pH 10.0,temperature 50℃,material ratio 0.8:1.0,reaction time 14 h.The effect of the material ratio and temperature on the reaction conversion rate was obvious.Study on the influence of material ratio and temperature on the reaction kinetics.The optimal range of large degree of reaction conversion rate and reaction rate:PDMS-E/gelatin=0.6:1.0～0.8:1.0（mol:mol）;temperature 50℃～55℃。Thermodynamic parameters were determined using the Arrhenius and Eyring laws.The reaction was accompanied by the increasing in endothermic and the decreasing in entropy.