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The curing processes of a novelly synthesized siloxane-containing epoxy resin (SE) and bisphenol A diglycidyl ether (CYD-128) were investigated using dynamic differential scanning calorimetry (DSC), and analyzed by three different methods. The results show that while SE has a lower initial curing temperature and a smaller pre-exponential factor than CYD-128, their curing processes belong to first order kinetic reaction. All the three dynamic methods verified mutually reveal that SE with more catalytic hydroxyls possesses lower activation energy and exhibits a stronger curing reactivity than CYD-128.

We investigated the effect of film-formation temperature andTg’s difference on the self-stratification gradient silicone film prepared by emulsion blend (poly(3-[tris(trimethyl silyloxy)silyl] propyl methacrylate-co-methyl methacrylate) /poly(butyl acrylate-co-methyl methacrylate) 50/50 by wt) (PTRIS-co-MMA/PBA-co-MMA) technique. The self-stratification film with gradient distribution of silicon was relatively easily obtained when both blend components could fully fuse to form a continuous film. Moreover, proper nonparallelTgs facilitated migration of the silicon component to the film-air interface during the film-formation and hence the gradient distribution was obtained. WhenTgof silicon-free component was 40°C, self-stratification gradient film with concentration of silicon components varying in a gradient-like manner along the overall transaction of the film was fabricated.

By varying the feed ratios of comonomers, butyl acrylate (BA), acrylic acid (AA), and methyl methacrylate (MMA), four acrylate macromolecular modifiers (AC730, AC532, AC235, and AC037) were synthesized by free radical copolymeration in ethnol. The effect of these modifiers on rheological behaviors of ultrafine CaCO3 aqueous suspensions was investigated on the basis of a series of rheological measurements. The results showed that comonomer compositions and amounts of modifiers have obvious effect on rheological behaviors of CaCO3 aqueous suspensions. In the case of AC730 and 0.2-0.4 parts of AC532, suspensions were pseudoplastic fluids, exhibiting shear thinning behavior; while in the case of AC235, AC037 and 0.6-1.4 parts of AC532, suspensions were dilatant fluids, exhibiting shear thickening behavior. Except the suspensions modified by 1.2 and 1.4 parts of AC730, the rheological data of other suspending systems could be well correlated with Herschel-Bulkley model. Optimum amounts of different modifiers were determined on the basis of rheological analysis, 0.8 parts for AC730, 0.6 parts for AC532 or AC235, and 0.4 parts for AC037.