Studies On Componentanalysis And Chlorine Water Resistance Of Polyolefin/Wood Flour Composites

Wood-plastics composites （WPCs） are a new kind of green materials, which aredeveloped rapidly recently. The appearance of WPC not only protects forest resources, butalso makes full use of waste plastics. As WPCs combine the characteristic of both wood andplastic, they are widely used in our life. WPCs are formed by thermoplastics and wood fiberswith some additives and fillers, sometimes because of the need of production and processing,it’s necessary to know the approximate proportion of wood and plastics in WPCs, but fewstudies about the quantitative analysis of WPCs were reported. What’s more, with the widelyuse of WPCs, they are used nearby the places like swimming pools, which containdisinfectant fluid. So it’s of certain practical significance to study the resistance of WPCs tochlorine water used in pools.First, the paper discussed the quantitative analysis of WPCs by preparing compositeswith known proportion, the research results showed that with the increase of wood flour inWPCs, the density of composites increased linearly; the TGA reveals that the char residual ofcomposites changes corresponding with the content of wood flour; and the DSC curveindicated that with the increase of wood flour, the melting enthalpy decreases linearly. As aconsequence, by these several methods above, it’s possible to conclude the proportion ofWPCs on the basis of WPCs of known proportion.Because of the existence of wood flour in WPCs, the chromophoric groups of lignin areeasily oxy-genated to fade. In this paper, we tested WPCs referring to the test standard for thecolor fastness of dyed fabric to cholrine water, systematically studied the resistance tochlorine pool water of WPCs. The results showed that with the increase of wood flour, thegrade of resistance to chlorine water color fastness reduced, surface wear and loss rate ofmechanical properties aggravated, and water absorption increased.The addition of inorganic filler can improve the resistance to chlorine water of WPCs, itshowed that the addition of nano-ZnO, nano-SiO₂, TiO₂can improve mechanical propertiesand vicat softening temperature of composites, effectively reduce the loss of mechanical properties and color fastness of composites after soaking in chlorine water. Alkali treatmenton wood flour can get rid of some lignin, raise the interface compatibility of composites, andeffectively improve the retention rate of mechanical properties and color fastness, amongwhich10%alkali treatment was more effective.MAPP is effective on resistance of chlorine water as it improves the interface bondingforce of plastic and wood flour. When adding wood flour to rPP, the results showed with theincrease of plant fiber, the tensile strength, flexural strength, flexural modulus and VST gotsignificant improvement, while the impact strength and MFR of WPCs decreased, what’smore, the retention rate of mechanical properties decreased after soaking in chlorine water.