Reparation And Properties Study Of The Antibacterial HDPE Resin

With the expanding range of application in various fields, high-density polyethylene (HDPE) has become one of the largest general-purpose plastic consumption due to its good toughness, low cost, easy molding and chemical resistance etc. As the HDPE does not have antibacterial function and the product surface which is susceptible to breed a large number of bacteria, mold has become disease source which seriously endanger people’s health for pathogens between persons, things, persons and things, researching and developing antibacterial HDPE has important practical significance for blocking the transmission of the disease and eliminate the infection source.Antibacterial HDPE studied were often prepared by blending HDPE with inorganic antimicrobial agent or organic small molecule antibacterial agent. Not only was it difficult for the antimicrobial agents to uniformly disperse in HDPE, but also the exudation antibacterial agent may depredated the antimicrobial performance and caused secondary contamination of the packaged products due to the poor compatibility of HDPE resin with antibacterial agents.The quaternary phosphonium salt of organic antimicrobial agent is a class of much-studied in recent years. The type of antimicrobial agent with strong electrical positive charge has a strong adsorption to the bacteria, causing the microbial cell wall structural damage and the contents spilled, showing good bactericidal, antibacterial properties.In order to overcome the shortcomings of the antibacterial of HDPE Blends and develop a new kind of HDPE with excellent antibacterial properties, antibacterial HDPE with chemical bond between phosphonium salt and HDPE molecular chains were prepared by continuous fusion reaction and dilution reaction system with HDPE and tributyl-3-[(and4-) vinyl benzyl] phosphonium chloride (TVBPC) as the main raw materials. The relationship between process conditions such as antimicrobial agent amount, reaction temperatures and initiator dosage and properties such as grafting rate, antibacterial properties, mechanical properties and melt flow rate (MFR) of the antibacterial HDPE were studied. The main results and conclusions are as follows:(1) The starting degradation temperature of TVBPC is293℃in air and343℃in argon. It has good processing stability. The minimum antibacterial concentrations are as follows:S.aureus:60mg/L, E. coli:15mg/L.(2) When the amount of TVBPC was less than3.2g per100g HDPE, grafting rate increased with the TVBPC amount increased. The grafting rate was of0.306%when adding3.2g TVBPC. The grafting rate was basically unchanged when the TVBPC amount increased then. The grafting rate increased first and then showed a decreasing trend with the increase of the amount of initiator when adding4.26g TVBPC. The highest grafting rate0.305%can be got when adding0.15g initiator. Grafting rate increase with the increase of temperature and the highest grafting rate appeared at220℃. The grafting rates of the antibacterial HDPE were4.8%and1.9%respectively when adding90g and71g TVBPC in dilution reaction system.(3).Antibacterial HDPE prepared by continuous melting reaction showed strong antibacterial (99%) against S.aureus and E. coli and anti-fungal performance when adding more than4.26g TVBPC per100g HDPE.(4) MFR of antibacterial HDPE prepared by continuous melt reaction was reduced significantly with the increase of the amount of TVBPC. The MFR of H3.20, H4.26and H5.33were3.81g/10min,2.73g/10min and2.43g/10min respectively. The MFR of the antibacterial HDPE decreased when the initiator amount decreased. The MFR of H0.10, H0.20and H0.25were7.07g/10min,2.67g/10min and1.46g/10min respectively. The MFR decreased with the increase of reaction temperatures. The MFR of H190is5.31g/10min. The MFR of H230is2.96g/10min. Antibacterial prepared by dilution reaction system was not changed significantly.(5) Compared with the raw material HDPE, the mechanical properties of antibacterial HDPE prepared by continuous melting reaction were reduced to a certain degree. The mechanical properties of H4.26were not changed significantly or to the degree within the error range.(6) Compared with the antibacterial HDPE prepared by blending with Benzyl (?)ibutyltin chloride phosphonium,the migration of antibacterial HDPE prepared by a chemical reaction with tributyl-3-[(and4-)vinyl benzyl] phosphonium chloride was significantly reduced in different media.