Study On Polyethylene Grafted With Maleic Anhydride And Its Compatible And Bonding Behavior

The reaction rule of LLDPE melt grafted Maleic anhydride(MAH) during reactive extrusion has been studied in a double screw reactive extruder in this paper. The effects of MAH content, tert-Butyl Perbenzoa (TBPB)content and screw speed and grafted accelerator and precrosslinked inhibitor on grafting degree and melt flow rate of the product were studied. The results showed that the optimal conditions were: MAH 2.0%, TBPB 0.15%, screw speed 60rpm, precrosslinked inhibitor 0.3%, grafted accelerator 6%.IR, GPC, DSC and electronic tensile testing machine were used to analyze physicochemical i properties of LLDPE-g-MAH product. The results showed that MAH grafted to LLDPE with single loop mainly and with a few of oligomer of MAH. Grafting degree of MAH was 1.52% by chemical titration. Melt temperature and crystallization temperature of grafted product decreased somewhat in comparison to raw materials(LLDPE). With improvement of grafting degree, tensile strength of grafted product increased, breaking elongation and flow performance of grafted product decreased,LLDPE-g-MAH was used to blend with composite of EVA/POE/AL(OH)3 as compatibilizer in this paper. Processability, mechanical properties and flame retardancy of EVA/POE/AL(OH)3/LLDPE-g-MAH were studied. The results showed that processability and mechanical properties of composite was improved dramatically. Compatibility of composite is better with higher grafting degree of LLDPE-g-MAH.LLDPE-g-MAH was used to blend with composite of PA66/LLDPE/Mg(OH)2 as compatibilizer in this paper. Processability, mechanical properties, impact behavior, and water absorption of PA66/LLDPE/Mg(OH)2/LLDPE-g-MAH were studied. The results showed that grafted product have great compatibilization on the blend of PA66/LLDPE/Mg(OH)2 and Integrated performance have been improved dramatically. When the compounding ratio of PA66/LLDPE/Mg(OH)2 was 60/40/30, addition proportion of LLDPE-g-MAH is 10. comparing with pure PA66, water absorption decreased by 36.6%; Tensile strength and elongation at break increased by 5.9% and 27.2% respectively in dry state; Tensile strength and elongation at break increased by 2.4% and 45.1% respectively in wet state; Impact strength and bending strength increased by 29.3% and 36.3% respectively in dry state; Impact strength increased 66% by in wet state.According to T end single-laps stretch shearing strength testing standard, adhesive property between carbon steel and LLDPE-g-MAH of different grafting degree were investigated. The highest shear strength (11.24Mpa) was obtained when the grafting degree was about 1.46wt% by Using LLDPE-g-MAH, and lap surfaces displayed cohesion failure that meant the bonding between LLDPE-g-MAH and carbon steel was firm while the bonding strength of LLDPE was not enough.