Interface Modification And Characterization Ot Bamboo Flour/PBS Composites With Poly(Dopamine)

In this thesis,the hot pressing variables were first studied.And then,using polydopamine to modify bamboo flour,the polarity of bamboo flour surface was reduced,and the interface compatibility between bamboo flour and polybutylene succinate(PBS)was enhanced.Different modification methods and modification were compared and studied.The influence of the conditions on the properties of bamboo-plastic composites(BPC)was tested by macroscopic test and microscopic analysis.The mechanism of polydopamin addition of bamboo-plastic composites was studied.The main findings are as follows:(1)On the basis of universal rotary design assembly experiment design,three regression models were established by using bamboo flour size and hot-pressing parameters as independent variables,and the mechanical properties of composites as dependent variables.The results showed that the bamboo flour size had the greatest influence on the tensile,bending and impact strength of composites,while the hot pressing pressure had the least influence on the above three indicators.There are interactions between the two factors of hot-pressing temperature and hot-pressing time on the tensile and flexural strength,and between bamboo powder particle size and hot-pressing pressure on the impact strength.The interaction between other factors is not obvious.(2)The in-situ deposition method is the best modification method for the preparation of bamboo-plastic composites using polydopamine modified bamboo flour.After modification by this method,the amount of free hydroxyl groups on the surface of bamboo flour rapidly decreases,the polarity decreases,and the interface of the composite material was significantly improved.Compared with the unmodified composites,the flexural strength,flexural modulus,tensile strength,tensile modulus and impact strength increased by 35.1%,23.9%,42.3%,and 39.9%,respectively.65.7%.(3)Dopamine solution concentration is the most important factor affecting the modification effect of composite materials.When dopamine concentration is 1.0 mg/mL,the composite exhibits the best interfacial properties.The bending strength,flexural modulus,tensile strength,tensile modulus and impact strength of the composites were increased by 34.2%,23.4%,65.5%,41.3%and 63.4%respectively compared to the unmodified composites.Significant improvement,but no significant change in the water resistance of composite materials.