Research On The Performance And Preparation Of Sisal/HDPE Composites

For the sake of enhancing environmental awareness and improving the agricultural economy,more and more scholars have begun to study the use of lightweight,high-strength,biodegradable hemp fiber to replace synthetic fibers to enhance polymers.However,the interface adhesion between the polarity hemp fiber and non-polar polymer is poor,affecting its reinforcing effect.In this paper,in the traditional alkali treatment process,the sisal fiber was subjected to alkali/MMA grafting,alkali/KH550 coupling composite treatment,and innovative use of alkali/PVA coating composite treatment,and an sisal/HDPE composite was prepared by extrusion process.The sisal fiber was characterized by FTIR and SEM.The mechanical properties,water absorption and thermal properties of sisal fibers and composites were examined and discussed.The microstructure of composite materials was observed and analyzed.Through the analysis of FTIR and SEM,it was found that the optimum process for alkali treatment of sisal fibers is: 10% Na OH solution treated 1h.The above three kinds of composite treatment can further modify the sisal fiber,improve the interface properties of the fiber and HDPE,and the effect of alkali/coating is the best,followed by alkali/coupling and alkali/grafting.The mechanical performance analysis results are as follows: The tensile strength of sisal fibers with alkali/coating was the highest,followed by alkali treatment,then followed by alkali/coupling and alkali/grafting treatment.When the sisal content was 12% and the length was 6mm,the mechanical properties of the composites were optimal.At this time,the tensile strength of untreated,alkali treated,alkali/grafted,alkali/coupled,and alkali/coated sisal/HDPE composite materials was increased by 6.3%,11.6%,15.7%,17.4%,26.2% respectively,compared to HDPE pure materials.The bending strength increased by 13.0%,18.5%,25.0%,26.5%,34.5% respectively.Alkaline/coating treatment was the lowest drop in impact toughness,followed by alkali/coupling and alkali/graft treatment,then followed by alkali treatment,and the drop at most was the untreated sisal/HDPE composite materials.The water absorption of composite materials is: After soaking for 240 h,the water absorption remained stable.At this time,the water absorption of the untreated sisal/HDPE composite materials was 2.03%,alkali treatment was 1.57%,alkali/grafting was 1.23%,alkali/coupling was 1.06%,and alkali/coating was 1.43%.Through TG and DSC analysis: The drying temperature of sisal fiber is 75?-100?,and the processing temperature should be less than 250?.The use temperature of Sisal/HDPE composites should not exceed 130°C.Sisal fiber,Composite material,Surface treatment,Mechanical properties,Water absorption...