Preparation,Structure And Properties Of SBS/PS/Sisal Fiber Composites

Sisal fiber is a natural,plant fiber that is renewable and naturally degradable.Sisal fiber is used to enhance the performance of polymer materials.In this paper,SBS/PS/SF composites were prepared by extrusion molding of sisal fiber(SF),styrene-butadiene thermoplastic rubber(SBS)and polystyrene(PS).It was studied using a universal material testing machine,a differential scanning calorimeter(DSC),a thermogravimetric(TG),and the like.The effects of SF dosage and SF treatment on mechanical properties,thermal properties,creep,stress relaxation and structure of composites were analyzed.The relationship between structure and properties of SBS/PS/SF composites is revealed.The results show that the mechanical properties test shows that the addition of SF improves the tensile strength and flexural strength of SBS/PS/SF composites,and reduces the strain size.The SF after treatment with silane coupling agent can be better enhanced.The impact strength of the composite;the bending strength does not change much.The thermal performance test showed that the addition of sisal fiber reduced the temperature of vicat of the composite material.Silane coupling agent treatment improved the thermal stability.Adding SF lowered the glass transition temperature.The glass transition temperature of the composite decreased with the increase of sisal fiber content,and the glass transition temperature of SF in the composite decreased after the treatment with silane coupling agent.The performance tests of the SBS/PS/SF composite after creep show that the strain of the composite increases with the increase of sisal fiber content,stress and creep time,and decreases with the increase of loading rate.Tensile strength and fracture strain were increased after creep test.The creep test reduced the glass transition temperature.When the sisal content is 10 parts,the sisal fibers in the composite material are evenly distributed and the boundaries are clear.When the sisal content is 30 parts,the sisal fibers in the composite material are unevenly distributed and agglomeration occurs.The creep experiment promotes the formation of silver streaks inside the composite,and the amount of silver streaks increases with the increase of stress.Part of the sisal fiber was separated from the composite matrix after creep experiments.The performance tests of the SBS/PS/SF composite after stress relaxation show that the stress of the composite increases with the increase of sisal fiber content,strain size,stress relaxation time and loading rate.The fracture strain after stress relaxation of the composite material first rises and then decreases.After stress relaxation,tensile strength increases first and then decreases?The fracture strain of the composites of 20 parts and 30 parts of sisal fiber content was reduced after the stress relaxation experiment under strain 100%.The fracture strain after stress relaxation test under other conditions was greater than that before the test.The glass transition temperature of the composite after stress relaxation is lower than before the stress relaxation.When the sisal content is 10 parts,the sisal fiber is evenly distributed,and the compatibility with the composite material is good.When the sisal content is 30 parts,the sisal fiber in the composite material is unevenly distributed and agglomeration occurs.The stress relaxation experiment promotes the formation of silver streaks inside the composite,and the amount of silver streaks increases with the increase of stress.After the stress relaxation experiment of some composite materials,the separation between the sisal fiber and the composite matrix occurs.