聚乙烯醇载入丝素的棉织物整理及生物降解性研究

将不同浓度丝素(SF)、聚乙烯醇(PVA)配制的共混溶液涂层于棉坯布上,再经烘焙、微波、超声波固定处理,研究了整理织物的土埋生物降解性和力学性能。结果表明:用SF和PVA涂层的棉织物的断裂强力和断裂伸长率都得到改善,同时涂层织物具有良好的生物降解性;微波固定处理后织物的降解程度大于超声波处理织物的降解性,烘焙处理织物的降解相对最小;整理液中丝素含量越高,涂层织物生物降解性越好。经过丝素/聚乙烯醇整理过的棉织物具有生物降解性和安全性,力学性能得到改善,具有较好的应用潜力。     

乙酰化淀粉/PBS制备生物降解塑料的研究

以玉米淀粉为原料,以醋酸酐为乙酰化试剂,氢氧化钠为催化剂,利用微波辐射技术制得乙酰化淀粉。用制备的乙酰化淀粉与聚丁二酸丁二醇酯(PBS)共混,制备了可生物降解热塑性淀粉塑料。研究了共混物制备的最佳工艺条件及其力学性能、生物降解性能及吸水性能,并对产物进行了红外光谱结构分析和表面电镜扫描分析。     

Application of the CONCAWE biodegradability test for oil products

Information on the biodegradability of an oil product (or its components) is needed for classification and labelling purposes. The extent to which a product can be broken down by microbial attack is usually determined using a ‘ready biodegradability’ test (e.g., OECD 301 Test Guidelines). However, these methods are stringent screening tests and can often underestimate the extent to which a product can be removed from the natural environment by biodegradation. CONCAWE (the European oil companies’ organisation for environment, health and safety) has recently developed a test for determining the potential (or ‘inherent') biodegradability of oil products. This is often more useful for assessing the likely impact of an oil product in the event of its release into the environment. This paper gives examples of CONCAWE test results for a number of base fluids and formulated products, and compares these results with those obtained in a ‘ready biodegradability’ test. Guidance is given on the applicability of data that has been obtained using the CONCAWE method.     

Recent trends in environmentally friendly lubricants

Many of the lubricants used in the world today cause environmental pollution through total‐loss applications, spillage, evaporation, and in other ways. To reduce this environmental damage, new lubricants that are rapidly biodegradable and ecologically non‐toxic have started to be developed and marketed. This paper discusses the introduction of environmentally friendly lubricants and their constituents, with particular emphasis on their environmental benefits, applications, the limits to their use, their technical performance characteristics, and relative cost aspects; many of these lubricants are based on vegetable oils and esters. Comparisons are also made in the paper with conventional mineral‐oil based materials.     

Advances in US Air Force hydraulic fluids

The US Air Force Wright Laboratory's Materials Directorate has been involved with the development and transition of advanced fluids and lubricants since the 1950s. The driving force for the development of new hydraulic fluids has primarily been and still is, improved fire resistance, although biodegradability and low toxicity have become increasingly important. This paper briefly traces the use of military aircraft hydraulic fluids from the beginning to the current state-of-the-art.     

Biodegradability of lubricant base stocks and fully formulated products

Increasing awareness of the environmental impact of consumer and industrial products has produced a demand for lubricants that biodegrade. There is a number of biodegradation tests that can be used on lubricants, although not all are always appropriate, as this paper explains. The CEC test is among the best known and is in use for both conventional and synthetic oils. There will, in future, be a greater movement to biodegradable oils in Europe, perhaps extending to all oils.     

Environmentally considerate ester lubricants for the automotive and engineering industries

Concern at the amount of lubricants lost in the environment has prompted the search for environmentally considerate lubricants, i.e. lubricants which biodegrade as a result of the biological action of living organisms. Various test procedures and parameters are discussed, and the performance of various lubricants, including synthetics, is presented.     

Water resistance,mechanical properties,and biodegradability of poly(3‐hydroxybutyrate)/starch composites

Composites of poly(3‐hydroxybutyrate), P(3HB), and starch were prepared by solution casting technique. To improve adhesion of starch to P(3HB), stearic acid was added as a compatibilizer and glycerol as a plasticizer. The water resistance, mechanical, and biodegradable properties of the P(3HB)/starch composites were studied. Diffusion and penetration coefficients of water increased with increasing starch content in the composites. The results showed that the elastic modulus and strain at rupture of the P(3HB)/starch composites were enhanced by increasing starch content upto 10 wt % and the tensile strength increased from 21.2 to 93.9 MPa. The presence of starch content higher than 10 wt % had an adverse effect on the mechanical properties of the investigated composites. The biodegradation rate using Actinomycetes increased proportionally to the starch content in the composite and accelerated in a culture medium of pH ≈ 7.0 at 30°C. Enzymatic degradation experiments showed that lipase produced by Streptomyces albidoflavus didnot degrade P(3HB)/starch composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Ultrasonic pre‐treatment of biological sludge: consequences for disintegration,anaerobic biodegradability,and filterability

BACKGROUND: Disintegration was developed as a pretreatment process for sludge to accelerate the digestion processes. Ultrasonic treatment may be a good alternative for sludge disintegration. In this study, different specific energy inputs ranged between 0 and 15 880 kJ kg^?1 and very low ultrasonic densities ranged between 0.04 and 0.1 W mL^?1 were applied to biological sludge for disintegration purposes. The potential for improving anaerobic digestion through ultrasonic pre‐treatment and the effect of ultrasonic pre‐treatment on the filterability characteristics of sludge were also investigated. RESULTS: 9690 kJ kg^?1 TS of supplied energy and very low power density of 0.09 Wm L^?1 are efficient for floc disintegration. For 9690 kJ kg^?1 TS, 44% higher methane production was achieved than with raw sludge as a result of biochemical methane potential assay. The supernatant characteristics of the sludge were also affected by the ultrasonic pre‐treatment. For 9690 kJ kg^?1 TS, the soluble chemical oxygen demand (SCOD), dissolved organic carbon (DOC), total nitrogen (TN), and total phosphorus (TP) in the sludge supernatant increased by 340%, 860%, 716%, and 207.5%, respectively. CONCLUSION: Ultrasonic pre‐treatment is an effective method for biological sludge disintegration even at very low ultrasonic density levels. It leads to increased anaerobic biodegradability but deteriorates the filterability characteristics of biological sludge. Copyright © 2009 Society of Chemical Industry