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反相悬浮聚合法合成可生物降解海藻酸钠高吸水性树脂 总被引:1,自引:0,他引:1
以丙烯酸(AA)和海藻酸钠(SA)为原料,用反相悬浮聚合法合成了聚丙烯酸钠/海藻酸钠高吸水性树脂。研究了海藻酸钠、引发剂(KPS)和交联剂(NMBA)用量、丙烯酸中和度、聚合反应温度等因素对树脂吸水率的影响以及树脂的生物降解性能。结果表明,当w(SA)=1.5%、w(KPS)=0.15%、w(NMBA)=0.1%、丙烯酸中和度为65%、聚合反应温度为75℃时,树脂对蒸馏水的吸水率为845 g/g,对生理盐水的吸水率为88 g/g,且能被土壤和微生物降解,w(SA)=10%的树脂在60 d内能够被芽苞杆菌降解52%,在土壤中能被降解36%,且降解速度随海藻酸钠质量分数的增加而加快。IR测定表明,树脂为丙烯酸盐与海藻酸钠的接枝共聚物。SEM测定表明,PAA/SA高吸水性树脂呈花瓣结构。 相似文献
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生物降解高吸水性树脂的研究进展 总被引:2,自引:0,他引:2
本文简述了高吸水性树脂的降解机理及影响因素,综述了国内外可生物降解高吸水性树脂的制备和研究发展状况,并预测今后研究方向和应用前景。 相似文献
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以甲醛和亚硫酸氢钠改性的羽毛蛋白(MFP)和丙烯酸(AA)为主要原料,N,N-′亚甲基双丙烯酰胺(NMBA)为交联剂,过硫酸钾-亚硫酸氢钠为引发剂,采用溶液聚合法制备改性羽毛蛋白接枝聚丙烯酸高吸水性树脂[P(MFP-g-AA)],并用土壤稀释液微生物法,研究了羽毛蛋白基高吸水性树脂的生物降解性能。考察了,制备水溶性羽毛蛋白的最佳工艺条件为ω(亚硫酸氢钠)∶ω(羽毛)为30∶100、氢氧化钠浓度为0.45%、反应温度96℃、反应时间2 h。在此条件下合成的[P(MFP-g-AA)]树脂生物降解性能最好,其凝胶薄片在5 mL土壤稀释溶液中放置25 d,凝胶表面基本被菌落覆盖。 相似文献
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聚丙烯酸钠盐高吸水性树脂 总被引:6,自引:0,他引:6
采用反相悬浮聚合法、逆相乳液聚合法或溶液聚合法合成自交联型、交联型聚丙烯酸钠盐高吸水性树脂,该树脂可吸收自身重量的几百倍的水。由于它的高吸水性,在压力下高的保水性和高的凝胶强度,被广泛用于纸尿布、卫生巾和土壤保水剂等。 相似文献
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聚丙烯酸钠高吸水性树脂的制备及性能研究 总被引:14,自引:0,他引:14
以环己烷为连续相 ,Span - 6 0为悬浮稳定剂 ,过硫酸钾为引发剂 ,N ,N′ 亚甲基双丙烯酰胺为交联剂 ,对反相悬浮聚合制备聚丙烯酸钠高吸水性树脂进行了研究。结果表明 ,影响合成树脂吸水率最主要的因素是交联剂质量分数 ,当交联剂质量分数为 0 .0 15 %时合成树脂的吸水率出现极大值 ,而且当反应温度控制在 6 5℃、引发剂质量分数为 0 .18%时所得树脂的吸水率可达 5 0 0g/g。对合成树脂吸水、保水性能的进一步测试发现 ,树脂在吸水的初始阶段吸水速率较快 ,随着吸水时间的延长逐步下降 ,当树脂吸水饱和后水分损失则很慢 ,在 84℃下 2 .5h仅损失 17%。 相似文献
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改性羽毛蛋白接枝丙烯酸高吸水性树脂的制备与吸水性能 总被引:2,自引:1,他引:1
以改性羽毛蛋白和丙烯酸为主要原料,N,N′-亚甲基双丙烯酰胺为交联剂,过硫酸钾-亚硫酸氢钠为引发剂,采用溶液聚合法制备了羽毛蛋白接枝聚丙烯酸高吸水树脂P(MFP-g-AA),并对其吸水性能及其影响因素进行了考察。结果表明:P(MFP-g-AA)吸去离子水倍率达到559.4 g/g,在0.3 MPa的压力下保水率达85%,且比聚丙烯酸树脂(PAA)具有更好的耐盐性能、保水性能和更宽的pH适用范围。与PAA相比,P(MFP-g-AA)在0.9%NaCl溶液和人工尿液中的吸水倍率分别由56.9 g/g和51.8 g/g提高到68.7 g/g和61.3 g/g,并且在pH=7~11的介质中都有优良的吸水效果。 相似文献
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Using recently introduced Automatic Continuous Online Monitoring of Polymerization reactions (ACOMP), the kinetics of acrylic acid polymerization was studied. ACOMP yields the absolute weight‐averaged mass (Mw), monomer conversion, and other quantities. As the initiator concentration increased, it was shown that the rate increased and the Mw decreased as in regular free‐radical polymerization. The effect of salt on acrylic acid polymerization in an aqueous solution was investigated. The polymerization rate and Mw both decreased with an increasing salt concentration. ACOMP molecular weights were also compared with size‐exclusion chromatography on aliquots periodically withdrawn during the reaction, and good agreement was found. The effect of the pH on the rate and the molecular weight was also investigated, and when the medium pH was changed from 2 to 5 with sodium hydroxide, the rate and Mw both decreased as the pH increased. Light‐scattering results of reaction end products in the reference solvent showed that molecules synthesized at higher pH were in a more expanded form. When equimolar sodium hydroxide was added to the acrylic acid (pH ? 5) and sodium acrylate formed, adding salt did not effect the reaction kinetics of the poly(sodium acrylate); its effect on the products was a relatively minor decrease of Mw. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1352–1359, 2004 相似文献
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壳聚糖/聚丙烯酸共聚物微球的制备及性能 总被引:1,自引:0,他引:1
以环己烷为油相,壳聚糖溶液为水相,运用反相乳液聚合法制得了具有pH敏感性的壳聚糖/聚丙烯酸共聚物微球。讨论了微球在pH=1~10缓冲溶液中的溶胀率变化,研究表明,微球在强酸性(pH≈1)和碱性(pH>7)条件下,溶胀率均在10倍以上;而在pH=2~6时溶胀较差,当pH=4时出现最低值,溶胀率低于1倍。光学显微镜所观察到的微球粒径均在40μm以内,且大小均匀。采用傅里叶红外光谱仪分析了不同配比样品特征峰的峰值和峰面积的变化。用722光栅分光光度计研究了共聚物微球包埋考马斯亮蓝的溶胀释放过程。 相似文献
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Poly(sodium acrylate) (PNaA) based nanocomposites were synthesized using different nanosilver loadings via redox solution polymerization at room temperature and under full exposure to the atmosphere. The nanocomposites exhibited increasing antibacterial activity with increased nanosilver content. Biocompatibility was determined using an MTT assay; no significant cytotoxicity was observed at the examined nanosilver loadings. Adhesion was measured using a tensile test and the stress versus strain curve showed an acceptable stress development in the model tissue using bioadhesive containing 2 wt% nanosilver. Introducing a second, more degradable polymer to the system as an interpenetrating polymer network enabled tuning the bioadhesive degradation rate. 相似文献
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以丙三醇三缩水甘油醚为交联剂制备聚天冬氨酸凝胶,考察了凝胶的热性能和黏弹性,并采用平板培养和液体培养法考察了凝胶的生物降解性。结果表明:丙三醇三缩水甘油醚交联凝胶具有良好的吸水保水性,且耐热性和黏弹性更优,平板试验证明凝胶也具有良好的生物降解性,液体培养法证明交联剂的种类和用量对凝胶的降解有较大影响,交联度均为60%的凝胶,交联剂为丙三醇三缩水甘油醚时第9天降解率为49.3%,较交联剂为乙二醇二缩水甘油醚制备的凝胶低9.2%,说明在相同交联度下丙三醇三缩水甘油醚形成的网络结构更致密;交联剂均为丙三醇三缩水甘油醚时,交联度为40%的第9天降解率为59.8%,较交联度为60%的凝胶提高了17.5%,交联度增加,降解速率降低。 相似文献
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As a biodegradable functional polymer, poly[(sodium acrylate)‐co‐(4‐vinylpyridine)] [P(SA‐co‐4VP)] containing a small amounts of 4‐vinylpyridine groups were prepared and their biodegradability, dispersity, and complex performance were analyzed. The polymers can be useful as detergent builders and dispersants. It was found that the biodegradation of P(SA‐co‐4VP) was more conspicuous when content of the 4‐vinylpyridine in the copolymer was larger. This indicates that the 4‐vinylpyridine, which acts as biodegradable segments, should be incorporated into the polymer main chain in such a manner that they are digested by activated sludge. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1953–1957, 1999 相似文献
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Thermal degradation and biodegradability of poly (lactic acid) (PLA) and poly (lactic acid)/corn starch (PLA/CS) composites with and without lysine diisocyanate (LDI) were evaluated by thermogravimetric analysis measurement and enzymatic degradation using Proteinase K and burial tests, respectively. Thermal stability was decreased by addition of CS and the composites with LDI showed higher thermal degradation temperature than those without LDI. In enzymatic biodegradation, the weight remaining of all samples decreased almost linearly with time. The addition of CS resulted in a faster rate of degradation and the composites with LDI were more difficult to degrade than those without it. In the composite without LDI, the degradation was faster at the interface between PLA and CS, showing deep and wide clearance, but degradation starting at the interface was not clearly observed in the composite with LDI. There was no considerable difference in molecular weight and distribution of the samples after enzymatic degradation. The lactic acid content of the water‐soluble product obtained after enzymatic degradation increased with degradation time. In burial tests, pure PLA was little degraded but the composites gradually degraded. The degradation of the composite without LDI was faster than that of the composite with LDI. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3009–3017, 2006 相似文献