| A series of novel acrylic polymers were synthesized by emulsion polymerization for car underbody coatings, which have no environmental pollution. The structure and properties of these polymers were characterized by GPC, 1HNMR, DSC, FT-IR, TEM, SEM, high quality microscope, rotation viscometer and INSTRON universal testing machine, etc. The reaction conditions of emulsion polymerization, the composition of comonomers, the growing history of latex particle, structure morphology, the controlling methods on particle size, the distributing rules of functional groups on the surface of latex particle, the performance character of polymer lattices, the coagulation states of latex particles, the arrangement of each copolymer layers, the cooperative effect of multi-layer, the plasticization mechanism between polymers and plasticizers were widely researched. The qualitative and quantitative relationship of polymer structure and properties, the optimization of sol's formulation and the molding technics of gel were also deeply and far-rangingly investigated. There are four stages on the development of these novel materials.Stage 1: Theory analysis and model establishment.Guided by the Fourth Statistics-JRG Sub-cluster Statistics Theory, the concept and the physical meaning of the sub-cluster parameter scales -L of the latex particle growing process were firstly denominated and its mathematic formula was theoretically determined and inferred in this dissertation. The model describing the relationship between the sub-cluster parameter scales and material's cohesive energy dissipation was established by scientific ideas and innovation. Following this theoretical model, four sorts of relations between the L scales and the cohesive energy dissipation were predicated. There are type 1: viscosity increasing and strength decreasing with L, type 2: viscosity increasing and strength increasing with L, type 3: viscosity decreasing and strength decreasing with L and type 4: viscosity decreasing and strength increasing with L. From the point of theory, the essential and intrinsic plasticization mechanism of plastisol-gel was perfectly researched and analyzed. The purpose of this project is to find and polymerize the fourth sort of materials.Stage 2: Elementary research on the emulsion polymerization and the properties of polymers.IIIIn this stage, the kinds and adding dose of emulsifier and initiator, the stirring speed, the reaction temperature and the monomer adding methods were carefully investigated and analyzed above conditions effect on the growing history of latex particle, particle size and its distribution, latex molecular weight and its distribution, latex viscosity. The best reaction mold was built for the emulsion polymerization, i.e. 0.5%~0.75% (related monomer weight) of AOT dosage, 0.03%~0.06% of KPS dosage, 200~300rpm, 80癈 reaction temperature, hungry semi-continuum monomer adding method, 20%~30% of monomer for seed polymerization. Under the optimum condition, a series of acrylic homopolymers and copolymers were synthesized. The mechanism of non- polarity plasticizers DOP and DINP, polarity plasticizer TCP and polymer was studied. It was shown that the storage stability of DOP and DINP sol is better than that of TCP sol, but the mechanical properties of DOP and DINP gel is worse than that of TCP gel. The simple structure of polymer determines the single application.Stage 3: Development of emulsion copolymer with high properties.Guided by the theoretical mold, through the method of " Molecular Design", a series of multi-functional core-shell polymers, ALMA-LIPN, HDDA-LIPN, DVB-LIPN core-shell polymers and reaction LIPN polymers were synthesized with the innovative ideas. The core-shell structure was characterized by TEM, SEM, DSC, etc. Results show that the emulsion polymerization is available and successful."Grads Design" was firstly put forward and successfully applied to multi-layer latex particle in this thesis. Respectively, different compositions of IBMA/MMA comonomer were polymerized as the first and...
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