The oxidation induction period that DSC checks polyethylene

Polyethylene is general thermoplastic plastic, produce more than 60 million tons every year, basically be carry ethylene monomer group and become. Familiar aggregate pattern has freedom radical polymerization, anion polymerization, ion to match a polymerization and cation polymerization. Because ethylene monomer structure is done not have other replace base, won't affect polymer catenary paragraph patulous stability, but method of group of avery kind of gets is different polyethylene breed. Through DSC test oxidation induction period can understand material to be being used and store the ageing circumstance of condition. Test condition: Temperature limits: RT…Quality of 230°C 　 kind measures: 3.25mg 　 crucible: Aluminous, n 　 rate-of-rise of air temperature: 10K/min, 2K/min 　 atmosphere: RT…150°C is nitrogen, 30ml/min; 50…230°C is air, 50ml/min To two kinds of polyethylene tubal material undertakes stability is compared oxidizing. Below nitrogen atmosphere, heat sample with 10K/min melt temperature above, the switch that sweep gas will be blown to become synthetic air in 150°C (N2:O2=80:20) . Add antioxidant to be able to lengthen material the counteractive time to oxygen, and ageing is to show polymer is right normally the counteractive time of oxygen drops. Sample 1 (blue curve) begin to produce oxidation reaction after 51.5min, and sample 2 (black curve) oxidation happens to react after 43.4min, because of this sample of 1 fight oxidation function much better.