Study On The Preparation And Properties Of HDPE/OBC And HDPE/OBC/PP-GF Blends

In this paper, high-density polyethylene (HDPE) as the matrix material, Olefin Block Copolymer(OBC) as toughening agent, ethylene-propylene-diene terpolymer (EPDM)-g-maleic anhydride(EPDM-g-MAH), ethylene-octane copolymer graft maleic anhydride (POE-g-MAH), ethylene-acrylic acid copolymer(EAA) as compatilizers, glass fiber reinforced polypropylene(PP-GF) as reinforcing material, strengthening and toughening modification are studied on the HDPE, using extrusion and injection molding process for preparing HDPE/OBC blends and HDPE/OBC/PP-GF blends. The mechanical properties of blends are tested by electronic universal testing machine and impact testing machine, crystallization property is discussed by differential scanning calorimetry(DSC), the hydrophilic properties is researched with contact angle machine, the plane of fracture is observed by scanning electron microscope(SEM), rheological behaviors of the blends is studyed by torque rheometer.The results show that:when adding18%(mass fraction) of the OBC, compared with the pure HDPE, the notched impact strength of the blends is increased by343.30%, elongation at break of the blends is increased by597.37%, and the bending strength and tensile strength decreased significantly; Due to the OBC, melt viscosity of the blends is added, but the melt flow ability is reduced, With the increase of EPDM-g-MAH, the interfacial interaction between HDPE and OBC is greatly enhanced, the degree of crystallinity is decreased significantly, melting temperature of the blends goes up, The addition of POE-g-MAH, the interaction between HDPE and OBC between molecular chains increase along with the compatilizer growth, the viscosity, the balance torque, the crystallinity and melting temperature of the blends are enlarged, the crystallization temperature decreases slightly; The addition of EAA, the crystallization temperature of the blends is decrease, the crystallization temperature, melting temperature of the blends is increased, the hydrophilic of the blends is improved; With the increase of PP-GF, the tensile strength and bending strength of the blends are greatly enhanced, When adding20%PP-GF to HDPE/OBC/POE-g-MAH, the tensile strength and bending strength increase by85.03%and219.23%respectively, when compared with pure HDPE, the tensile strength and bending strength are increased by23.19%and96.79%, the notched impact strength increased299.18%, mechanical properties of the blends are excellent.