Heat-Resistance Modification And Properties Study Of Nylon6and High Density Polyethylene

Nylon6(PA6) is an important crystalline engineering thermoplastic with many valuableproperties including high tensile strength, good solvent resistance, and abrasion resistance.PA6has been widely used in television, automobile，mechanical industry, and other electricapplications. However, due to the poor heat resistance, high water absorption, lowdimensional stability, the range of applications of pure PA6are restricted. High-densitypolyethylene (HDPE) occupies a pivotal position in the plastics industry. And it is widely usedfor its excellent overall performance and low-cost in agriculture, industry, packaging industry,and daily life applications. However, because of its linear molecular chain structure, HDPE’sheat resistance and wettability properties are poor, which limits its use in lithium batteryseparator material. In order to improve heat resistance and other properties of PA6and HDPE,the PA6/PPO alloy and crosslinked-HDPE material were developed herein.In the first part, we prepared PA6/PPO blend system. PPO is employed to improve themechanical property and heat resistance. Because PA6and PPO are incompatible polymers,we added8900,1125, PPO-g-MAH as compatilizers to enhance the interface adhesion andpromote phase dispersion of PA6/PPO alloy. In addition, the influence of mechanicalproperties, heat resistance, process ability, solvent resistance and water absorption wereinvestigated in terms of resin component, different kinds and contents of compatibilizers. Theresult shows that the heat resistance, tensile strength, water absorption properties can beimproved by adding proper content of PPO. And suitable compatilizers can enhance theinteractions between PA6and PPO, which results in the enhancement of mechanicalproperties. By adding5~10wt%8900or PPO-g-MAH,5wt%PPO, we can obtain thePA6/PPO alloy with high impact strength and excellent heat resistance properties.Fluorescence spectroscopic technique was adopted to investigate the compatibility of thealloy systems.In the second part, crosslinking agent (initiator) TBHB was used to initiate peroxidecrosslinking reaction of HDPE. In addition, inorganic fillers were added to improve heatresisitance and electrolyte wettability of HDPE. The influence of mechanical property, heatresistance, electrolyte wettability and crystallization property were investigated in terms of crosslinking agent, crosslinking condition and inorganic fillers. The result shows that, suitablecrosslinking time, crosslinking temperature and crosslinking agent can improve themechanical property and heat resistance. And after annealing treatment, the impact strength,heat resistance and electrolyte wettability were improved. Al2O3can increase the electrolytewettability and heat resistance, but decrease the mechanical property to some extent. Bycontroling crosslinking agent at0.1-0.3wt%, crosslinking time within24h, crosslinkingtemperature at120℃and Al2O3content within15wt%，we can develop high-perofrmancecrosslinked-HDPE.