Application Of Recycled Acrylonitrile-Butadiene-Styrene Polymer In Fused Deposition Molding Filament

Due to the increasing scarcity of petroleum resources and the aggravation of white pollution,more and more attention is paid to the development of recycled plastics.Recycling of waste plastics has been a hot issue.Researching the recycling of plastics,especially their high value application,is of great significance to solve plastic pollution,save resources and protect the environment.Acrylonitrile-butadiene-styrene(ABS)is a typical engineering polymer.Due to its excellent mechanical and processing properties,ABS takes a large share in the raw material market.However,the reuse of recycled ABS(r ABS)faces a series of problems including toughness loss,molecular weight decrease and surface quality weakening,which limit the application of r ABS.The way of traditional plastic recycling can solve the r ABS mechanical defects to some extent while few people mention the combination of r ABS and 3D printing technology.It's worth to notice that ABS is one of the commonly used material for 3D printing.Turning r ABS into 3D printing materials has not only a return on profits but also a great reliability.The author intends to study the problems and solutions of r ABS used in 3D printing technology.The main contents and achievements are as follows:(1)Since carboxyl groups is formed during the processing of r ABS,the styrene-acrylonitrileglycidyl methacrylate(SAG)copolymer is directionally prepared.The copolymer can be used as a chain extender of r ABS to increase molecular weight of r ABS and a compatibilizer of r ABS/PBT blends to improve compatiblility.Furthermore,the effects of the chemical structure of SAG and the SAG content in r ABS/PBT/SAG blends on morphology,rheology and mechanical properties of the r ABS/PBT/SAG blends were studied.It is found that the rheological behavior of the blends during processing can be controlled by selecting appropriate concentration of reactive group and changing the reaction blending sequence,which is to achieve finer phase morphology of the blends.This is helpful to obtain regenerated r ABS with excellent performance.The modified r ABS can be further applied to fusion deposition modeling(FDM)technology.(2)The SEBS and SEBS-g-MAH were selected to toughen r ABS.The mechanical properties of r ABS toughened by elastomers with different components were studied.The results show that compared with r ABS/SEBS blend,r ABS/SEBS-g-MAH blend has more excellent tensile strength,ductility and impact resistance,especially in improving impact performance.Microscopic observation shows that good phase interface and local co-continuous structure are the fundamental reasons for improving the mechanical properties of the r ABS/SEBS-g-MAH blends.Through the observation of impact fracture surfaces,it can be found that simple peeling cannot provide contribution for impact modification.The stronger interfacial adhesion and deformation of elastomer are the effective ways to absorb a large amount of impact energy.(3)The filaments with excellent mechanical properties and molding properties in r ABS reinforcement and toughening modification are prepared and further applied to 3D printing.The printing properties and mechanical properties of printed products were evaluated.The results show that the filament needs enough strength,rigidity and flexibility to push the molten plastic out of the nozzle.Meanwhile,the printing materials should have appropriate viscosity and cooling rate to make the melt flow out smoothly and solidify quickly.In addition,sufficient diffusion time is needed to make the filament bonding completely.The internal stress in the curing process should be reduced as much as possible to prepare qualified 3D printed products.The significance of the research results in this paper is to show how to design and evaluate the process of recycled ABS to prepare 3D printing materials,which has certain novelty and practical significance and contributes to the high-value application of recycled plastics.