Highly Filled PLA-based BPC Preparation And Bamboo Charcoal Modification

The development of environmentally friendly and biodegradable materials is currently a major worry due to the increasing severity of environmental pollution and the dwindling resources of the earth.The central government’s call to replace plastic with bamboo and achieve green and sustainable development can be met by using bamboo processing wastes filled with PLA to create biodegradable composites that not only have improved mechanical properties and cost less to produce.The effects of the compounding process,bamboo raw material morphology,bamboo fiber content,and bamboo charcoal modification on the mechanical properties,water absorption,interfacial wettability,melt flow,thermal stability,and interfacial bonding morphology of the composites were examined in this paper,which used the hot pressing method to create bamboo fiber/PLA composites.The following are the paper’s major conclusions:(1)The composite process had a significant impact on the composites’ overall characteristics,and the high temperature blending-hot pressing method(HH)produced composites with better mechanical characteristics,moisture resistance,melt flow,and thermal stability than the mechanical blending-hot pressing method(JH).(2)The following raw materials were used to create the composites,and their mechanical qualities were graded from best to worst: bamboo fiber(BF),60-90 long mesh bamboo granule(BM),120-150 mesh bamboo powder(BP),and bamboo shavings(BS).According to HH,BF’s greater aspect ratio contributed significantly to its higher bending strength of 40.11%,tensile strength of 36.30%,and impact strength of123.23% compared to BSPC.Yet compared to BSPC,BMPC,and BPPC,the thermal stability of BFPC was decreased,and the rate of water absorption at 288 hours was3.40% greater than that of BMPC.The bending properties of the composites in different forms and blending methods meet the standard of LY/T2565 "bamboo-plastic composites",but the impact properties are met only by BFPC.(3)The flexural and tensile strengths of the composites improved with the addition of bamboo fiber,but the impact strength and thermal stability declined.The elastic modulus and tensile modulus were highest at 60% filling of bamboo fiber,which increased100% and 71.22%,respectively,compared with pure PLA.The melt index of the composites increased with the addition of bamboo fiber,with the greatest melt index recorded at 40% bamboo fiber content,and a pattern of first increasing and then decreasing was seen.(4)The mechanical properties of the composites exhibited a trend of increasing and then decreasing with the addition of bamboo charcoal;the best result was obtained at a bamboo charcoal addition of 0.5%,which increased the bending strength,tensile strength,and impact strength by 6.82%,16.91%,and 6.41%,respectively,in comparison to the mechanical properties of the composites without bamboo charcoal addition.Meanwhile,the inclusion of a small quantity ofbamboo charcoal can raise the surface contact angle,enhance thermal stability,and somewhat lower the composites’ water absorption.(5)The impact of bamboo charcoal particle size on the mechanical properties of composites is significant;too large of a particle size cannot fill the gaps in the composites,and too small of a particle size is prone to agglomeration,which is not conducive to improving the mechanical properties of the composites.Particle sizes between 200 and 400 mesh can form a better interfacial bond with the composites and obtain the best mechanical properties.The impact on the composites’ surface contact angle was negligible.The improvement of thermal stability is positively impacted by the bamboo charcoal’s small particle size..