PBAT全生物降解地膜在土壤试验中的降解行为研究

研究了以聚己二酸/对苯二甲酸丁二酯(PBAT)为主要原料的全生物降解地膜在实地埋土降解实验过程中的降解行为.采用红外光谱、X射线光电子能谱、凝胶渗透色谱、热失重分析、扫描电子显微镜对PBAT薄膜在降解过程中化学结构、表面元素、热稳定性、表面微观形貌以及分子量的变化进行分析.结果表明,随埋土时间的延长,PBAT地膜红外光...     

上海有机所研制出无公害降解地膜

无须进行任何人工处理便能自行降解或粉化的无公害地膜 ,日前已由上海有机化学研究所研制成功并通过鉴定 .这种无公害降解地膜以聚乙烯为基质 ,再添加光氧化降解剂、氧化降解促进剂、生物降解剂和降解控制剂等降解助剂组成 ,采用独特的工艺制备 ,成本低廉 ,适合大规模生产 .科研人员将研制的 10余吨地膜在上海郊区 4 0 0 0亩蔬菜、瓜果和花卉地试用 ,其保温、高产效果和普通地膜一样 .覆盖 3～ 6个月后 ,留在地里的地膜在阳光照射下能自行降解崩裂或完全粉化 ,被压在地里的那部分地膜也能自行粉化 ,并且不污染土质 .(摘自“中国化工信息网”…     

聚酯热氧化降解的速度和机理

本文推导了求PET热氧化降解速度常数的公式。采用热重法、粘度法和羧端基法,对不同催化稳定体系的PET,求出了热氧化降解速度常数。根据实验结果,讨论了热氧化降解机理。     

微生物降解土壤残留农药的研究进展

综述了在环境中降解土壤农药的微生物、微生物降解农药的机理、在自然条件下影响微生物降解农药的因素以及农药微生物降解研究方面的新技术和新方法。在农药的微生物降解研究中,应重视自然状态下微生物对农药的降解过程,分离构建由天然的微生物构成的复合系,利用微生物复合系进行堆肥或把堆肥应用于被污染的环境。     

施胶剂对纤维素复合材料降解的影响

用土埋法研究了施胶剂对纤维素复合材料降解性能的影响。结果表明 :与未施胶样品相比 ,施胶样品在前期降解较快 ,而在后期降解较慢。从三个月降解的最后结果来看 ,添加施胶剂对材料降解有一定负影响。未施胶样品通过土埋法降解三个月 ,其降解率为 68% ,而施胶样品降解率在 55%～ 60 %之间。从经济和降解率考虑施胶量为 2 .9%是适宜的     

含磷阻燃共聚酯热氧化降解过程分析

研究了一种含磷阻燃共聚酯在空气条件下的热氧化降解过程 ,得出了该种阻燃共聚酯的热氧化降解规律 ,为阻燃共聚酯的后加工工艺条件的选择提供了重要依据     

聚氨酯材料的降解机理及其稳定剂

综述了聚氨酯(PU)材料的光降解、热氧化降解、水解等降解机理,以及用作光稳定剂、热氧化稳定剂、水解稳定剂的产品种类及其协调作用.聚氨酯材料的使用环境不同,降解机理也不同,正确选用稳定剂并进行应用是提高PU材料性能的一种简单而有效的手段.     

聚乙烯醇降解特性研究

采用凝胶色谱法（GPC）和紫外分光光度法（UV）研究了聚乙烯醇（PVA）微生物降解和化学氧化降解效果。GPC实验表明，PVA经过本实验室筛选的微生物菌株降解后，保留9min左右产生了一个小相对分子质量的峰，其峰面积约占总面积的一半；UV实验也表明了PVA在降解菌株的作用下，其浓度呈下降趋势；采用Fenton试剂（FR）对PVA进行预先氧化处理，然后再进行微生物降解。结果表明FR预处理有利于PVA的快速有效降解。     

淀粉粒径对微细化淀粉/LDPE共混体系降解性能影响

采用光降解、土埋降解和环境降解法，研究了不同粒径微细化淀粉／LDPE共混膜的降解性能。结果表明，淀粉粒径的降低促进LDPE的环境降解基体的形成，加速淀粉和LDPE的环境降解速度。微细化淀粉／LDPE共混体系的降解是环境促降解因子共同作用的结果。     

聚丁二酸丁二醇酯在不同土壤环境中的降解研究

本文考察聚丁二酸丁二醇酯(PBS)在不同土壤中的降解情况,从当地取堆肥土、污泥土、垃圾土和花园土对PBS进行土埋法降解试验,通过测定降解过程中的失重率变化和对PBS降解前后表面形态观察,得出PBS在不同土壤中的降解顺序,为塑料的可降解性能的进一步研究奠定基础。     

碳酸钙和淀粉对聚乙烯薄膜降解性能影响研究

目的:研究淀粉和CaCO3对塑料薄膜的降解影响。方法:将CaCO3填充膜和淀粉填充膜经自然曝露、紫外线照射和土埋处理,测试拉伸强度、断裂伸长率和分子量的变化。结果:自然曝露30d,CaCO3填充膜和淀粉填充薄膜的平均拉伸强度分别下降80.8%和54.4%,平均断裂伸长率分别下降99.4%和98.3%,分子量分别下降25.3%和13.8%;紫外光照120h,CaCO3填充薄膜和淀粉填充薄膜的平均拉伸强度分别下降14.7%和45.9%,断裂伸长率分别下降97.3%和97.0%,分子量分别下降66.7%和48.3%;土埋203d,CaCO3填充薄膜和淀粉填充薄膜的失重率分别为2.2%和15.0%。结论:CaCO3和淀粉均能加速聚乙烯塑料薄膜的降解,其中CaCO3的光降解性能方面优于淀粉,而淀粉的生物降解性能优于CaCO3。     

Control of biodegradability of poly(3‐hydroxybutyric acid) film with grafting acrylic acid and thermal remolding

Radiation‐induced graft polymerization of acrylic acid (AAc) on poly(3‐hydroxybutyric acid) (PHB) film was carried out and the resulting film was thermally‐remolded. The PHB films grafted with AAc (PHB‐g‐AAc) having a degree of grafting higher than 5% completely lost the enzymatic degradability. The enzymatic degradability of the grafted film was recovered by thermal remolding. The highest enzymatic degradation rate was observed at degree of grafting of 10% after thermal remolding. The PHB‐g‐AAc films and thermally‐remolded PHB‐g‐AAc films were characterized by contact angle and differential scanning calorimetry. The enzymatic degradability of PHB‐g‐AAc films was lost by the grafted AAc, which covered the surface of PHB film. The acceleration of enzymatic degradation in the remolded PHB‐g‐AAc films was mainly caused by decrease of crystallinity of PHB by dispread of grafted AAc during thermal remolding. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3856–3861, 2006     

微生物对稠油降解、降粘作用研究进展

稠油因其有高粘、流动性差、不宜开采的特点成为石油开采运输的研究重点;微生物降解稠油技术因高效、不污染油品,近几年来研究进展较大。目前,解烃菌的菌种数量虽然众多,但是这些菌种对地层、油藏的伍配性太强,只适应特定的油品;降解胶质、沥青质方面微生物存在着一定难度,这类菌种较少而且作用周期较长。论述了影响稠油流动性的因素、近几年来微生物降解稠油的研究进展,展望了日后的微生物降解稠油的研究方向。     

南极拟酵母脂肪酶对聚丁二酸丁二酯薄膜的降解研究

以聚丁二酸丁二酯(PBS)薄膜为降解底物,利用南极拟酵母脂肪酶（Lipozyme CALB）对其进行降解研究;考察了pH值、温度、酶浓度以及降解时间对Lipozyme CALB降解PBS薄膜的影响,并通过扫描电子显微镜、差示扫描量热仪、热重分析仪及质谱分析仪等对PBS薄膜以及PBS的降解产物进行了表征分析。结果表明,在酶浓度为20 U/mL,反应温度为50 ℃,pH值为 7.0的条件下,经24 h的降解,PBS薄膜（3 cm×1 cm×0.5 cm）的降解率可达90 %以上;随着降解时间的延长,薄膜表面明显发生了降解并形成孔洞,且PBS的相对结晶度呈现上升趋势,PBS薄膜的热稳性逐渐上升; PBS的降解产物为1,4丁二酸和丁二酸丁二醇二聚体。     

剑麻纤维增强聚乳酸复合材料酶降解研究

通过热压成型的方式制备了剑麻纤维增强聚乳酸（PLA/SF）复合材料,并通过K蛋白酶降解方式研究了该复合材料的生物降解性能,利用差热扫描量热仪测试分析了复合材料在酶降解过程中的非等温结晶性能。研究发现,剑麻纤维的加入加快了聚乳酸及其复合材料的降解速率,且随着剑麻纤维含量的增加,其降解速率提高;剑麻纤维的加入对聚乳酸的结晶性能有一定的影响,进而也影响了复合材料的酶水解速度。     

Effect of electron beam radiation on the performance of biodegradable Bionolle-jute composite

To study the radiation effect on the physical, thermal, mechanical and degradable properties of biodegradable polymer Bionolle (chemosynthetic polyester poly(1,4-butylene succinate)), Bionolle films prepared by compression molding process and were irradiated with electron beam (EB) radiation of different doses. Gel content was found to increase with increase of radiation dose. Tensile strength of Bionolle was enhanced when Bionolle film was exposed under 20 kGy radiation. The loss of tensile strength of both unirradiated and irradiated Bionolle is 70% and 8% due to thermal aging at 70°C for 30 days. Both irradiated and unirradiated films of Bionolle were subjected to different degradation test in compost (soil burial), enzyme and storage degradation both in outdoor and indoors conditions. The loss of weight due to soil (compost) degradation test decreased with increase of radiation dose. The loss of weights of irradiated samples were found to be very less within the first three months of compost degradation. After 120 days, tensile strength of the Bionolle films irradiated at 20 kGy and 100 kGy were 68 MPa and 40 MPa, respectively, compared to the value (30 MPa) of the unirradiated Bionolle samples. Loss of tensile strength of irradiated Bionolle due to storage degradation like in roof, ground and indoors was minimum compared to unirradiated Bionolle. The weight loss due to enzymatic degradation was found to be decreased with increase of radiation dose. The tensile strength of jute reinforced Bionolle composites (23 wt.-% jute content) irradiated at 20 kGy was found to be higher (22%) than that of an unirradiated composite.     

Biodegradation of low‐density polyethylene‐banana starch films

Films were prepared by extrusion using acetylated and oxidized banana starches at different concentrations mixed with low‐density polyethylene, and their biodegradation (buried in soil) at different storage times was studied. Morphological, thermal, and mechanical characteristics of the films after degradation were tested. Films made of acetylated banana starch degraded most rapidly and those prepared with oxidized starch had the slowest degradation time. The type of chemically modified starch plays an important role in degradation of film. Burying the films produced a decrease in degradation temperature at the longest storage time, and there was a longer interval in the films prepared with native banana starch, followed by those made of acetylated starch. The buried in soil films had a broad phase transition and, consequently, an increase in enthalpy. This is due to degradation of amorphous starch zones with an increase in the crystallinity. Electron scanning microscopy analysis revealed greater degradation at longer storage time and a more marked effect in the films made of modified banana starch. Mechanical properties of the films were affected by degradation, and these varied depending on the modified banana starch used. The use of biodegradable polymers such as chemically modified banana starch might be feasible for making films with a high rate of degradation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

油剂处理对PAN原丝热性能的影响

通过热重和热质联用手段研究了氨改性聚硅氧烷油剂处理对PAN原丝热性能的影响。结果表明,油剂在纤维表面的附着可以提高原丝的开始分解温度,并且在300℃以后,对原丝热性能的影响开始明显化,它还使原丝分解产物的逸出产生延迟,并且浓度有所下降。这是由于油剂薄膜层的存在对原丝热解过程的传热和传质两方面均有阻碍作用引起的。     

Degradation in soil behavior of artificially aged polyethylene films with pro‐oxidants

Bio‐based, biodegradable in soil, as well as degradable polyethylene mulching films with pro‐oxidants, have been introduced in the market in an effort to deal with the serious problem of managing plastic waste streams generated from conventional mulching films. In a previous experimental investigation, a series of naturally degraded under water melon cultivation conditions linear low density polyethylene (LLDPE) mulching films with pro‐oxidants, buried in the field for 8.5 years, were recovered intact even though undergoing a continuous slow abiotic degradation in soil. The aim of the present article was to simulate the behavior of the LLDPE mulching films with pro‐oxidants under a much longer time‐scale (e.g. some decades). Toward this purpose, samples of LLDPE with pro‐oxidants film were artificially degraded to simulate severe degradation/fragmentation of these films while been buried in the soil for many years, following the end of the cultivation season. Further degradation of these severely degraded samples was investigated by burying them in the soil over a period of seven years. During this burial period, all degradation parameters and their evolution with time were measured. The artificially degraded LLDPE film samples with pro‐oxidants, in contrast to the naturally degraded film that remained intact for 8.5 years, were gradually transformed into tiny micro‐fragments in the soil. These fragments, through a continuing abiotic degradation process under natural soil conditions are eventually transformed into invisible micro‐fragments. The fate of these micro‐fragments and their long‐term impact to the environment and human health is unpredictable. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42289.     

细菌纤维素增强改性聚碳酸亚丙酯复合材料的制备及性能

将细菌纤维素(BC)作为增强材料加入聚碳酸亚丙酯(PPC)基体中,采用溶液浇铸法制备了PPC/BC复合薄膜材料,研究了BC用量对PPC拉伸性能、热稳定性能及降解性能的影响。结果表明:随着BC用量的增加,PPC/BC复合薄膜的拉伸强度和热稳定性能明显提高,降解速率减慢。