在西藏拉萨地区中对滚塑包装箱专用高密度聚乙烯(HDPE)进行了18个月的自然老化试验，以研究其在极端气候环境下的老化特性与规律。采用衰减全反射红外光谱(ATR-FT-IR)和 X 射线衍射技术分析了材料老化前后微观结构指标羰基指数、羟基指数、支化程度、断链程度、不饱和度变化趋势及晶体结构变化特点，进一步确定其老化行为，并通过对氧化特征谱带洛伦兹分峰拟合，探究氧化产物的生成规律。结果表明，材料老化初期支化和氧化作用显著，老化中期支化和断链作用仍为主要的老化行为，氧化作用一定程度上放缓，老化后期断链则占主导地位。老化过程中晶体结构基本不变，晶胞参数小幅度变化，老化中氧化产物以酮羰基为主，γ内酯羰基为二次氧化产物，且二者生成趋势相反，酯羰基和醛羰基的增长出现前期增长缓慢后期加速的特点。
In order to study the aging profile of high density polyethylene (HDPE)used as rotational packaging case under the extreme conditions,the nature exposure test was carried out for 18 months in Lasa Tibet.The structural changes of carbonyl index,hydroxyl index,branching degree,chain scission degree,unsaturation de-gree and crystal structure were monitored,by attenuated total reflection infrared spectroscopy (ATR-FT-IR) and X-ray diffraction,to determine the degradation behavior.Finally,the character peaks of oxidation products were analyzed by Lorentz distribution technology.The results showed that the chain branching & oxidation play a leading role in the early aging progress.Then the chain branching & chain breaking gradually takes place in the interim aging progress with a slow oxidation progress.The chain breaking is predominant in the later aging progress.The crystalline structure is basically unchanged after aging,but the cell parameters are weakly changed.The ketone is the primary oxidation product,with opposite generate trend to the secondary oxidation product,γ lactone.The oxidation products of aldehyde and ester increase slowly in the early aging progress, then rapidly.
参考文献
| [1] | Anne Ammala;Stuart Bateman;Katherine Dean .An overview of degradable and biodegradable polyolefins[J].Progress in Polymer Science,2011(8):1015-1049. |
| [2] | Masaki Sugimoto;Akihiko Shimada;Hisaaki Kudoh.Product analysis for polyethylene degradation by radiation and thermal ageing[J].Radiation Physics and Chemistry,2013:69-73. |
| [3] | Pages P.;Saurina J.;Colom X.;Carrasco F. .FTIR AND DSC STUDY OF HDPE STRUCTURAL CHANGES AND MECHANICAL PROPERTIES VARIATION WHEN EXPOSED TO WEATHERING AGING DURING CANADIAN WINTER[J].Journal of Applied Polymer Science,1996(2):153-159. |
| [4] | Yang R;Liu Y;Yu J;Wang KH .Thermal oxidation products and kinetics of polyethylene composites[J].Polymer Degradation and Stability,2006(8):1651-1657. |
| [5] | Kupper L.;Gulmine JV.;Janissek PR.;Heise HM. .Attenuated total reflection infrared spectroscopy for micro-domain analysis of polyethylene samples after accelerated ageing within weathering chambers[J].Vibrational Spectroscopy: An International Journal devoted to Applications of Infrared and Raman Spectroscopy,2004(1):63-72. |
| [6] | Gauthier, E.;Laycock, B.;Cuoq, F.J.J.-M.;Halley, P.J.;George, K.A. .Correlation between chain microstructural changes and embrittlement of LLDPE-based films during photo- and thermo-oxidative degradation[J].Polymer Degradation and Stability,2013(1):425-435. |
| [7] | Zerbi G;Gallino G;Del Fanti N et al.Structural depth profiling in polyethylene films by multiple internal reflec-tion infra-red spectroscopy[J].POLYMER,1989,30(12):2324-2327. |
| [8] | Yang R;Yu J;Liu Y;Wang KH .Effects of coupling agents on the natural aging behavior and oxidation profile of high-density polyethylene/sericite composites[J].Journal of Applied Polymer Science,2008(1):610-617. |
| [9] | Carrasco F.;Pascual S.;Colom X.;Pages P. .Artificial aging of high-density polyethylene by ultraviolet irradiation[J].European Polymer Journal,2001(7):1457-1464. |
| [10] | Chinese meteorological data sharing service system[EB/OL].http://cdc.cma.gov.cn/home.do,2014-03-06. |
| [11] | Lu, L.;Li, X.;Gao, J. .Evaluation of aging behavior of medium density polyethylene in natural environment by principal component analysis[J].Journal of Applied Polymer Science,2012(1):19-23. |
| [12] | J.V. Gulmine;P.R. Janissek;H.M. Heise;L. Akcelrud .Degradation profile of polyethylene after artificial accelerated weathering[J].Polymer Degradation and Stability,2003(3):385-397. |
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