红外光谱法研究降解PE膜的生物降解引发过程

利用红外光谱法研究环境降解PE薄膜的光氧降解性,其最终产生羧酸的反应历程表明,红外光谱法是评价此类降解膜生物降解引发过程的一种简便而有效的方法。研究结果还表明,胺烷基二茂铁衍生物和新型烷基二硫代氨基甲酸铁是此类PE膜的两类生物降解有效引发剂;而新型烷基二硫代氨基甲酸镍可有效地控制其生物降解引发过程;含有它们的PE薄膜具有较好的环境降解性。     

光—生物降解PE塑料配方设计和评价研究

研究了光－生物降解ＰＥ母料及其薄膜制品复合组分配方体系组成设计，经物性，光降解诱导期，光降解终点，光降解眩和生物降解性等性能指标的试验评价，其结果表明：含光敏剂和淀粉为关键组分的－类光－生物降解ＰＥ薄膜比单纯的光或生物降解ＰＥ薄膜具有更好的光－生物降解性；另一类含光敏剂，促氧化剂和生物降解增敏剂的物降解ＰＥ薄膜，在日光作用后，也具有较优的光一生物降解性。     

普通聚烯烃类塑料生物降解研究进展

介绍了高分子材料生物降解的概念、生物降解的作用方式,影响生物降解的因素,并且分析了高分子聚合物生物降解的研究现状,从添加易生物降解的填料法和添加光氧助剂-生物降解法这两个方面总结了普通聚烯烃类塑料生物降解研究进展,指出了今后研究的重点。     

含淀粉与光敏剂的LDPE膜可控光生物降解

研究了含超淀粉及硬脂酸铁或Ｎ,Ｎ－二正丁基二硫代氨基甲酸铁／Ｎ,Ｎ－二正丁基二硫代氨基甲酸镍光敏剂的低密度聚乙烯膜光氧化降解羰基指数,粘均分子量和真菌侵蚀（级）的变化。结果表明,只需在ＬＤＰＥ膜中添加５％－１５％淀粉和０．１％－０．３％ＦｅＳｔ３或０．０５％－０．２０％ＦｅＤＢＣ／ＮｉＤＢＣ光敏剂,在自然曝露条件下可控ＬＤＰＥ膜的使用寿命 。     

淀粉粒度对可生物降解聚乙烯膜性能的影响

探讨了淀粉 /聚乙烯共混可生物降解膜的性能受淀粉粒度控制问题以及在环境中降解机理 ,并认为对于各种可生物降解薄膜 ,需要在考虑等同使用寿命条件下来判别其生物降解能力 ,才会更加客观。     

可生物降解PVA膜的研究进展

综述了可生物降解聚乙烯醇(PVA)膜的研究进展,简要介绍了薄膜用PVA的改性方法、应用和存在问题,并展望了未来可生物降解PVA膜的发展.     

可生物降解淀粉基PE农用地膜的研制

本文主要介绍彩淀粉接枝改性的技术研制可降解淀粉基ＰＥ膜的工艺过程，并对其生物降解性能进行评价。     

巴斯夫推出可生物降解农用地膜塑料

相对于采用普通聚乙烯（PE）塑料制成的农用薄膜而言,采用EcovioFMulch制成的薄膜可以生物降解。     

高级氧化法提高难降解有机污水生物降解性能的研究进展

近年发展起来的高级氧化法能有效提高难降解有机污水的生物降解性能,形成了高级氧化法与后续生化技术相结合的处理技术,具有投资少、处理成本低和适用范围广等优势,显示出了广阔的应用前景。通过简要介绍化学催化氧化法、电催化氧化法、光化学氧化法、超声氧化法和湿式氧化法等高级氧化法的原理及研究现状,重点阐述国内外高级氧化法在提高污水生物降解性能方面的研究成果,得出了各技术的特点及其在应用中存在的主要问题,并展望了高级氧化法的发展方向。     

Biodegradation of oxo‐biodegradable polyethylene

Biodegradation of polyethylene and oxo‐biodegradable polyethylene films was studied in this work. Abiotic oxidation, which is the first stage of oxo‐biodegradation, was carried out for a period corresponding to 4 years of thermo‐oxidation at composting temperatures. The oxidation was followed by biodegradation, which was achieved by inoculating the microorganism Pseudomonas aeruginosa on polyethylene film in mineral medium and monitoring its degradation. The changes in the molecular weight of polyethylene and the concentration of oxidation products were monitored by size exclusion chromatography and Fourier transform infrared (FTIR) spectroscopy, respectively. It has been found that the initial abiotic oxidation helps to reduce the molecular weight of oxo‐biodegradable polyethylene and form easily biodegradable product fractions. In the microbial degradation stage, P. aeruginosa is found to form biofilm on polymer film indicating its growth. Molecular weight distribution data for biodegraded oxo‐biodegradable polyethylene have shown that P. aeruginosa is able to utilize the low‐molecular weight fractions produced during oxidation. However, it is not able to perturb the whole of the polymer volume as indicated by the narrowing of the polymer molecular weight distribution curve toward higher molecular fractions. The decrease in the carbonyl index, which indicates the concentration of carbonyl compounds, with time also indicates the progress of biodegradation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Multiple Exothermic Oxidation Behaviour of Polyethylene

The change of shape patterns of the oxidation peak on differential thermal analysis curves of a series of formulations of polyethylene has been investigated. The unstabilised sample exhibits two oxidation peaks. When a chain-terminating antioxidant and dilaurylthiodipropionate were added to polyethylene, it was found that as the concentration of dilaurylthiodipropionate increases, the second oxidation peak reduces in size. In many instances when the amount of dilaurylthiodipropionate reaches 0.3% (by weight), the second oxidation peak disappears. The influences of processing method and outdoor exposure on the peak shape have also been examined. The effectiveness and consumption of antioxidants during weathering is clearly shown by the shape change of the oxidation peak on the differential thermal analysis curves.     

Integrated Wet Air Oxidation and Biological Treatment of Polyethylene Glycol-Containing Wastewaters

The treatment of a model wastewater containing polyethylene glycol (PEG) of molecular weight 10000 in an integrated wet air oxidation–aerobic oxidation process was investigated. Partial wet air oxidation under mild operating conditions was capable of converting the original polymer to lower molecular weight compounds, such as oligomers and short-chain organic acids. The effect of molecular weight on the aerobic biodegradability of polyethylene glycol was assessed by performing shake flasks experiments with various polyethylene glycols in a molecular weight range from 200–35000 and it was found that biodegradability generally decreased with increasing molecular weight. Aqueous solutions of PEG 10000 were subjected to continuous wet air oxidation at a temperature of 423 K and a residence time of 30 min and the oxidised effluents were then subjected to subsequent continuous aerobic oxidation at residence times varying between 0·5 and 4 days. Simultaneously, continuous aerobic oxidation experiments on solutions of PEG 10000 were performed and used to compare the efficiency of the integrated treatment process with that of the direct biological treatment. Partial pretreatment by wet air oxidation under mild operating conditions resulted in effluents whose biodegradation rates were significantly higher than those of the original, unoxidised wastewater, as assessed by total organic carbon (TOC) removal rates. The original wastewater was practically non-biodegradable at a 0·5-day residence time with direct biological treatment, while an 80% TOC removal was achieved when biological treatment was coupled with a preceding wet air oxidation step. Conversely, with a 4-day residence time for the direct biological treatment the original wastewater was only partially degradable with 60–70% TOC removal recorded; with the integrated treatment process at a 4-day residence time in the bioreactor the overall TOC removal was greater than 90%. © 1997 SCI     

TNT生物降解的可能途径

综述了上前国内外报导 的氧化塘生物降解ＴＮＴ的几种不同途径 。提出了废水中ＴＮＴ生物降解的新途径：即ＴＮＴ首先转变为３－Ａ，２－Ａ，２－ＤＡ，２，４－ＤＡ，再转变为邻苯二甲酸酯类、酚类，以后转变直链酯类，最后ＴＮＴ完全初降解。     

测试条件对测定管材类聚乙烯树脂等温氧化诱导时间的影响

等温氧化诱导时间是检测聚乙烯燃气管材的一项重要指标。文章以4种管材类聚乙烯树脂为样品,分别分析了测量温度和试样制备方式对管材类聚乙烯树脂等温氧化诱导时间测试结果的影响。根据评价效果和实际测试需要给出了适合管材类聚乙烯树脂等温氧化诱导时间测定的试验条件。对规范塑料产品等温氧化诱导时间的测量工作具有借鉴意义。     

聚乙烯防雾滴棚膜研究进展

介绍了聚乙烯防雾滴棚膜的防雾滴机理及技术。综述了国内外防雾滴棚膜的发展状况     

Diffusion of an Antifogging Agent in Polyethylene Film

The diffusion of an antifogging agent, EO/PO (epoxyethane/epoxypropane) copolymer, through a polyethylene PE film was studied using a simple experimental system. It was found that the temperature, concentration of antifogging agent, crystallinity of PE film and film thickness affect the diffusion process.     

防雾滴剂在聚乙烯农膜中的扩散过程研究

The diffusion of an antifogging agent, EO/PO (epoxyethane/epoxypropane) copolymer, through a polyethylene PE film was studied using a simple experimental system. It was found that the temperature, concentration of antifogging agent, crystallinity of PE film and film thickness affect the diffusion process.     

聚乙烯收缩膜的吹塑工艺研究

通过在聚乙烯吹塑加工过程中改变吹胀比、牵引比、霜高线高度等工艺条件,考察其对收缩率的影响;并引人膜泡冷却时间的概念,以量化这些工艺条件的影响。结果表明,薄膜纵、横向拉伸的大小和冷却时间的长短共同决定薄膜的收缩率;拉伸越大,薄膜收缩率越大;膜泡冷却时间越短,薄膜收缩率越大。且膜泡冷却时间为6--10、时,纵、横向收缩率比较适合。     

抗氧剂在聚乙烯耐老化农膜中的应用

本文说明了聚乙烯耐老化农膜生产时,应用抗氧剂的重要性和必要性。同时说明了应如何选择抗氧剂。