In this paper, a novel hydrophobic modified cationic polyacrylamide flocculant P(AM⁃DAC⁃APG) was successfully synthesized by copolymerization of acrylamide (AM) as the main monomer, acryloxyethyl trimethyl ammonium chloride (DAC) as the cationic monomer and alkyl glycoside (APG) as the hydrophobic monomer, initiated by low⁃pressure ultraviolet light. FTIR, SEM and 1H⁃NMR were used to observe and analyze its chemical structure and surface morphology. The effects of other factors such as total monomer concentration and initiator concentration on the polymerization were studied. Optimum polymerization conditions were confirmed as total monomer concentration of 35.0%, initiator concentration of 0.2%, illumination time of 90 min, m（AM）/m（DAC）of 3, hydrophobic monomer concentration of 2.0%, urea concentration of 3.0%. The novel hydrophobic modified polyacrylamide flocculant with intrinsic viscosity and cationic charge density of 1 384.8 mL/g and 5.091 mmol/g was obtained under these conditions.

MnFe2O4/TiO2 Fenton⁃like photocatalyst was successfully prepared by sol⁃gel method, the structure and morphology of the sample were characterized by XRD, SEM and UV⁃vis. MB was used as the target pollutant for degradation, and the photocatalytic properties of products with different doping amounts were investigated in visible light. The results show that: The degradation rate of TMF Fenton⁃like photocatalytic reaction to MB is up to 96.8%, under the optimum conditions, in the iodine⁃tungsten lamp with a light source of 300 W, the doping amount of MnFe2O4 to TiO2 is 2%, the mass of catalyst is 60 mg, pH=11, and the concentration of H2O2 is 8 mmol/L . Under the same conditions, compare with the undoped pure TiO2, the catalytic performance of MnFe2O4/TiO2 for MB under visible light is significantly improved.

The expansion dryer is the critical equipment for the finishing unit of rubber plant.It can remove 90% moisture from the rubber melt. Based on FLUENT software, the flow of rubber melt in the runner of expansion dryer was numerically analyzed. Under different production conditions, such as pressure difference between inlet and outlet, screw speed and so on, the flow law of rubber melt in the runner of expansion dryer was analyzed according to the velocity and pressure distribution nephograms, so as to improve the quality of rubber.

The expansion dryer was the critical equipment for the finishing unit of rubber plant. It could take off 90% moisture in the rubber melt. The flow behavior of rubber melts in the channel of the expansion dryer was analyzed by FLUENT. Observing the nephogram of the distribution of rubber melts speeds and stress nephogram, the flow rule of rubber melts in the expansion dryer was analyzed. The following research directions were indicated.