环境友好型改性蓖麻油热固性塑料的研究

以蓖麻油为原料,通过与马来酸酐半酯反应合成了改性蓖麻油树脂(HEAMACO).该树脂分子链上含有较多的可参与白由基反应的双键,经与稀释单体笨乙烯共聚合,可形成一种具有生物降解性的热固性塑料。详细研究了固化反应温度、苯乙烯的含量、引发剂和促进剂的含量对所制得的热固性材料的物理力学性能的影响。结果表明:该材料的玻璃化温度(Tg)及力学性能均随笨乙烯含量的增加而升高,而且增加引发剂和促进剂的用量也有利于材料性能的提高。随苯乙烯含量的不同,该固化材料具有从软质到半硬质材料的特性,Tg介于10~60℃之间,土埋实验初步表明该材料具有良好的生物降解性。     

医用镁及镁合金表面可生物降解有机高分子涂层的应用

近年来,镁及镁合金由于其生物可降解性和良好的生物相容性,在医疗器械领域的应用获得了迅速的发展,然而过快的降解速率限制了其在临床上的应用。可生物降解有机高分子涂层是一种降低镁及镁合金降解速率的有效表面改性方法,同时还可赋予镁及镁合金医疗器械多种功能性。首先综述了可降解有机高分子涂层对镁及镁合金耐腐蚀性能和生物相容性的影响。可降解聚合物涂层能阻碍腐蚀性介质与基体的接触,从而延长其降解时间。而涂层对基体的保护提供了碱性较弱的环境,更利于细胞的生长增殖;同时涂层随着基体一起降解,可降低聚合物长期存在生物体内可能引发炎症反应的风险。此外,对聚合物涂层在骨科以及心血管支架领域的应用以及进展进行了综述。一方面,可降解聚合物涂层能显著延长镁及镁合金在生物体内的作用时间;另一方面,涂层可以作为载体材料通过携带具有不同功能的试剂或者药物实现医疗器械的功能化,如促进骨愈合和药物的可控释放。因此,可降解聚合物涂层在镁和镁合金器械领域必将起到无可替代的作用。     

Fabrication of Biodegradable Polyurethane Foam Scaffolds with Customized Shapes and Controlled Mechanical Properties by Gas Foaming Technique

Poly(ε-caprolactone) (PCL)-based polyurethane (PU) foam scaffolds with different mechanical properties are fabricated using a gas foaming technique to use as porous substitutes for ear or bone with cartilage. PCL diol or triol is used as a polyol in PU foam for biocompatibility and biodegradation, with an aqueous gelatin solution as a blowing agent. The highly porous inner and outer structures of the scaffolds are developed by employing a silicone surfactant and sulfuric acid, respectively. The PU scaffolds prepared by PCL diol show ductile and flexible properties, whereas the PU scaffolds prepared by PCL triol exhibit high compression strength. In vitro test reveals the low toxicity of the PU scaffolds and the high ALP activity of MC3T3-E1 cells in the PU scaffold prepared by PCL triol. By taking advantage of the difference in mechanical properties, customized PU scaffolds with ear or bone shapes are fabricated using a silicone mold. The PU scaffolds with two compartments of PCL diol and triol (corresponding to cartilage and bone, respectively) are fabricated as a substitute for bone with cartilage. It is believed that the PU scaffolds with highly porous structure and controlled mechanical properties have wide potential application for tissue engineering.     

聚对苯二甲酸-共-丁二酸丁二醇酯的研究及产业化现状

介绍了生物可降解材料脂肪族/芳香族共聚酯聚对苯二甲酸-共-丁二酸丁二醇酯(PBST)的合成工艺技术及基本性能,综述了近年来国内外PBST的研究现状和产业化现状.PBST的合成工艺主要是酯交换法和直接酯化法,酯交换法原料成本高、副产物分离较难、合成的PBST相对分子质量低;直接酯化法可以得到纯度较高的PBST,副产物只有...     

聚碳酸亚丙酯生物降解渗水地膜的研制及性能分析

为了解决农田白色污染问题,选用大分子聚碳酸亚丙酯（PPC）和聚己二酸丁二醇酯/对苯二甲酸丁二醇酯（PBAT）两种生物降解材料以及强力渗水助剂为原料制备PPC生物降解渗水地膜,采用多次吹膜测试法对地膜的配方和工艺方案进行了优选,并通过万能拉力测试机、紫外老化试验箱等对地膜的力学性能和降解性能进行了表征。结果表明,按照优选方案A₉和A₂的配方和工艺,结合渗水地膜加工工艺,可以成功制备厚度为（0.007±0.002） mm的薄型PPC生物降解渗水地膜;以A₉和A₂为基础并进行优化处理后的工艺技术试制的6个产品的力学性能均能够达到GB/T 35795—2017标准要求;0.007 mm PPC生物降解渗水地膜60 d后开始出现横纵向裂口,180 d后降解率为77.06 %,365 d后降解率为95.72 %。     

环境友好半合成切削液的研制

选用无毒或低毒性添加剂,在系统考察基础油、缓蚀剂、表面活性剂以及油性剂、极压抗磨剂和其他添加剂的配伍性能的基础上,按照微乳液调配理论,研制了一种环境友好型水基半合成切削液,并对其抗磨减摩、防锈、生物降解等综合性能进行了评价,实验室结果表明：该切削液具有优良的防锈性、抗腐蚀性、润滑性和其他综合性能。生物降解试验表明研制的半合成切削液生物降解性能较好,生态毒性低,达到了设计要求,是一种理想的环境友好润滑剂。     

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。     

有机化合物好氧生物降解性的研究方法

对合成有机化合物的生物降解性研究,可以预测各类化合物在环境中的滞留与影响,为某些化合物的生产和应用以及排放条件提供立法依据,并对开发更有效的生物处理技术具有重要意义。本文从合成有机物生物降解性研究的意义、研究方法等方面,介绍了国内外在这方面研究工作的进展情况。同时,对皮革化工材料生物降解性研究提出了建议。     

Combined γ-ray irradiation-activated sludge treatment of humic acid solution from landfill leachate

Humic acid, which is a typical microbially refractory organic substance, was extracted from a landfill leachate. The humic acid solution (COD = 367 mg 1⁻¹; TOC = 293 mg 1⁻¹; BOD = 27 mg 1⁻¹) was applied to a batch scale activated sludge treatment after the modification of its biodegradability by γ-ray irradiation. The BOD increased to 64 mg 1⁻¹ by irradiation of 15 kGy (1.5 Mrad), while the COD and TOC decreased to 231 and 230 mg 1⁻¹, respectively. When the irradiated sample was treated with an activated sludge, the BOD decreased rapidly in 2–3 h to about 15 mg 1⁻¹ which was a similar value as the unirradiated sample was treated. The elimination efficiency of TOC by the sludge treatment was approximately equal to that obtained by irradiation of 15 kGy. These facts suggest a utility of applying microbial processes after radiation treatment of microbially refractory wastewaters.     

Anaerobic toxicity and biodegradability of pulp mill waste constituents

Batch bioassays have been conducted to characterize the response of methanogenic bacteria to several constituents of sulfite evaporator condensate. The results can be grouped into three ranges with increasingly severe consequences to anaerobic reactors: a low concentration, no effect range; a medium concentration range where methanogenesis is temporarily interrupted or slowed down, but may return to normal; and a high concentration range where methanogenesis is permanently inhibited. In some cases the toxicant was metabolized when present in the lower concentration ranges. There was also evidence that mechanisms other than fermentation to methane were significant in accounting for removal of the toxicants from solution. Organisms acclimated to low concentrations of a toxicant are better able to withstand a shock load of that toxicant than are unacclimated organisms.