聚丙烯酸钾/平菇菌糠复合高吸水树脂制备及性能研究

采用微波辐射引发合成了聚丙烯酸钾(PAA-K)/平菇菌糠新型高吸水树脂,研究了平菇菌糠、引发剂和交联剂相对丙烯酸(AA)的比率以及丙烯酸中和度、微波辐射功率等对高吸水树脂吸水性能的影响,同时采用傅里叶红外光谱仪、元素分析仪、热重分析仪、扫描电子显微镜等仪器分析手段对复合高吸水树脂的分子结构、热稳定性、表面形态及元素分布进行表征。结果表明,在最佳合成条件下,复合高吸水树脂的最大吸液倍率在蒸馏水中为827 g/g,在浓度0.9 %的NaCl溶液(生理盐水)中为87 g/g;在高速离心机转速为6000 r/min下,50 min复合高水树脂的失水率仅为5.2 %。     

聚丙烯酸-海藻酸钠吸水树脂的制备及性能研究

以丙烯酸为单体,海藻酸钠为接枝物,添加丙烯酰胺,通过溶液聚合法制备复合型耐盐高吸水性树脂。研究了聚丙烯酸-海藻酸钠高吸水树脂的吸水性能。结果表明,在蒸馏水、生理盐水中吸水倍率分别达到830 g/g、81 g/g。天然高分子海藻酸钠具有很好的耐盐性,海藻酸钠的加入,提高了高吸水性复合材料的耐盐性。     

聚丙烯酸钾/白灵菇菌糠复合高吸水树脂的制备与性能

采用氢氧化钾(KOH)中和丙烯酸(AA),通过微波辐射加热引发合成了聚丙烯酸钾(PAA-K)/白灵菇菌糠(WMCPN)复合高吸水树脂。系统地研究了菌糠、引发剂和交联剂相对AA的比率,微波辐射功率及丙烯酸中和度对高吸水树脂性能的影响。结果表明,菌糠用量为50 %(相对AA质量,下同)、引发剂用量为1.33 %、交联剂用量为1.0 %、微波功率为450 W及AA中和度为80 %时复合高吸水树脂吸液倍率最大,在蒸馏水中为974 g/g,在0.9 %氯化钠(NaCl)溶液中为59 g/g;WMCPN与PAA-K实现了共聚反应;在离心机转速为6000 r/min下,50 min复合高吸水树脂的失水率为6.2 %。     

KHA/PPA缓释控肥料的制备及性能

以丙烯酰胺(AM)、丙烯酸(AA)、腐植酸钾(KHA)、多聚磷酸铵(PPA)为原料,N,N′-二亚甲基双丙烯酰胺(MBA)为交联剂,过硫酸钾(KPS)为引发剂,采用水溶液聚合法合成了具有吸水保水功能的腐植酸多聚磷酸铵缓释控肥料(HA/PPA).探讨AM与AA质量比、KHA用量、PPA用量、AA中和度、KPS用量、MBA...     

聚丙烯酸/高岭土复合高吸水树脂的制备及结构性能研究

以丙烯酸和高岭土为原料,采用水溶液聚合法制备了聚丙烯酸/高岭土复合高吸水树脂,对其结构性能进行了研究。结果表明:当丙烯酸质量分数为20%,高岭土质量分数为10%,过硫酸钾质量分数为0.13%,N,N'-亚甲基双丙烯酰胺质量分数为0.2%,反应温度为80℃,反应时间为3 h时,所制的聚丙烯酸/高岭土复合高吸水树脂表面形貌良好,高岭土分散均匀,吸水倍率为132 g/g,保水率为93.9%,凝胶形变量为2.3 mm;聚丙烯酸高吸水树脂的吸水倍率为121 g/g,保水率为82.5%,凝胶形变量为7.1 mm;高岭土的加入不仅提高了聚丙烯酸树脂的吸水倍率、吸水速率与保水率,且显著提高了聚丙烯酸树脂的凝胶强度。     

粘土/天然橡胶复合材料的制备与性能研究

采用分散剂多聚脂肪酸盐水杨酰亚胺制备粘土/天然橡胶(NR)复合材料,并对其性能进行研究。结果表明:当水杨酰亚胺用量为0.015份、粘土用量为50份、不添加偶联剂或环氧化天然橡胶时,所制得的粘土/NR复合材料具有优异的拉伸性能、抗撕裂性能、耐磨性能以及较低的压缩生热;粘土在NR基体中均匀分散。     

聚氨酯（PU）／聚丙烯酸酯（PA）的合成及在皮革涂饰剂领域的应用研究

本文研究了乳胶型互穿网络聚合物LIPN聚氨酯（PU）／聚丙烯酸酯（PA）的合成机理、工艺及其在皮革涂饰剂领域的可用性。     

SBS/粘土纳米复合材料的制备和性能研究

通过溶液插层法制备了苯乙烯—丁二烯—苯乙烯聚合物(SBS)／粘土纳米复合材料，并用X射线衍射透射电子显微镜分析其纳米分散结构及形态。研究结果表明：所得复合材料为插层型纳米复合材料；与SBS相比，SBS／粘土纳米复合材料断裂拉伸强度和300％定伸强度显著提高，储能模量明显提高。     

腐植酸钾-凹凸棒-聚丙烯酸复合树脂的吸液性能

以过硫酸钠-亚硫酸氢钠为引发剂,N,N’-亚甲基丙烯酰胺为交联剂,采用静态溶液聚合制备了腐殖酸钾-凹凸棒-聚丙烯酸复合吸水树脂。研究了凹凸棒、腐殖酸钾对复合吸水树脂吸蒸馏水倍率、吸盐水倍率以及吸水速率的影响,并对比了各种复合吸水树脂的吸液性能。     

聚丙烯酸钠制备吸水膨胀天然橡胶的研究

采用氧化还原引发体系,引发丙烯酸钠聚合并接枝到天然橡胶分子链上,并采用硫磺硫化体系进行硫化,制备高性能吸水橡胶。通过考察单体用量和多种配合剂对吸水橡胶的吸水和力学性能的影响,得出单体用量的增加引起吸水橡胶的物理机械性能的降低,但吸水性能得到了提高。FTIR分析可知,产物是天然橡胶和聚丙烯酸钠的接枝共聚物。TG分析表明天然橡胶和聚丙烯酸钠的接枝共聚物的热力学稳定性得到很大程度的提高。     

熔融插层法制备聚丙烯／粘土复合材料及性能研究-I增容剂对聚丙烯／粘土复合材料力学性能的影响

通过添加不同含量的粘土制备了三个不同类型（PP／DK1,PP／PPMA／DK1,PP／PPMA＋DK1）纳米粘七／聚丙烯复合材料。使用力学性能测试对实验样品进行力学性能分析,结果表明：相对于纯聚丙烯,复合材料的拉伸强度、断裂伸长率随着粘土含量的增加呈先增加后下降趋势;而随着PPMA量的增加,基体的总体性能都呈现下降的趋势。     

SBS/黏土纳米复合材料的制备方法探究

探索了SBS／黏土纳米复合材料的制备工艺，将经过特殊有机化剂有机化的有机土按4％添加量改性SBS橡胶，采用先高速剪切再超声波处理工艺，能有效地提高SBS的性能。     

Factors affecting N release of urea from reactive layer coated urea

An experimental fertilizer called reactive layer coated urea (RLCU) has been developed by coating urea with a mixture of diisocyanate and polyol in the presence of a catalyst. The hard, durable layer that is formed on the granule conveys slow-release character to the product. A series of soil incubation tests were conducted under simulated upland conditions for periods up to 56 days to study the effect of factors such as temperature, pH, soil moisture, and organic C additions on N release. The N release rate from RLCU was shown to be increased with increasing temperature and decreasing coating thickness. It was unaffected by the addition of lime to raise the pH or organic carbon sources to increase microbial activity. Although a slight effect of soil moisture was noted, it was not pronounced. Urea release tended to be in two stages — a constant diffusive stage in which, it is postulated, urea was still dissolving within the granule and diffusing to the soil at a constant rate and a slower logarithmic stage where the rate of release decreased with time.     

Preparation and Properties of Vinylester Resin/Clay Nanocomposites

Summary: Vinylester resin matrix composites were fabricated with 1, 3, 5 and 10 wt.‐% loadings of organoclay. The composite samples were subjected to various characterization techniques like X‐ray diffraction, flexural testing, dynamic mechanical analysis, thermogravimetric analysis, and scanning electron microscopy. The clay samples as well as the clay–resin composites were investigated by X‐ray diffraction. From the shift in the peak positions and the change in d‐spacing values, it was evident that there was intercalation in the 10 wt.‐% composites, whereas exfoliation occurred in the 1, 3, and 5 wt.‐% composites. The flexural strength and the breaking energy of all the composites were decreased compared with the unfilled resin, but there was an increase in flexural modulus value by 13%. From the dynamic mechanical analysis of the 3 and the 5 wt.‐% composites, it was observed that the loss modulus value was higher in the 3 wt.‐% composites, but the glass transition temperature was slightly higher in the 5 wt.‐% composites. Thermal degradation behavior was also improved in the 5 wt.‐% composites compared with the 3 wt.‐% composites.

Fracture surface of 3 wt.‐% clay filled vinylester resin matrix composite in different magnifications.     

Polyamide 66/Clay Nanocomposites via Melt Intercalation

Polyamide 66/clay nanocomposites (PA66CN) were prepared via a melt compounding method using a new kind of organophilic clay, which was obtained through co‐intercalation of epoxy resin and quaternary ammonium into Na‐montmorillonite. The dispersion effect of silicate layers in the matrix was studied by means of XRD and TEM. The silicate layers were dispersed homogeneously and nearly exfoliated in the matrix as a result of the strong interaction between epoxy groups and PA66. The mechanical properties and heat distortion temperature (HDT) of PA66CN increased dramatically. The notched Izod impact strength of PA66CN was 50% higher than that of PA66 when the clay loading was 5 wt.‐%. Even at 10 wt.‐% clay content, the impact strength was still higher than that of PA66. The finely dispersed silicate layers and the strong interaction between silicate layers and the matrix reduced the water absorption, at 10 wt.‐% clay content; PA66CN only absorbs 60% water compared with PA66. The addition of silicate layers changed the crystal structure in PA66CN.     

膨润土/羧甲基纤维素钠水凝胶的制备及其应用

通过化学交联技术制备了一种生态友好和成本低廉的BT-g-CMC水凝胶，并对其结构和形貌进行了表征，并将其用于废水中回收磷和缓释磷肥。吸附研究表明，当CMC/BT的质量比值为1时，在298 K下水凝胶对H2PO4-具有良好的亲和力，吸附容量为18.78 mg/g，吸附平衡时间为120 min；其次，将富含磷的BT-g-CMC1.0水凝胶用作缓释肥料（SRFs），结果表明，SRFs具有优良的保水和缓释能力。盆栽实验表明，SRFs对蔬菜生长具有促进作用。土壤修复实验表明，当SRFs用量为0.3g，浸出3次时，对土壤中Cr(Ⅲ)的固定化率为82.9%。因此，SRFs具有广泛的工业和绿色农业应用。     

粘土／丁苯橡胶纳米复合材料的制备和性能

通过两种方法制备了粘土均匀分散于橡胶中的纳米复合材料。电子显微镜显示粘土以单层和多层的形式分散于橡胶基体中,Ｘ－光衍射显示了粘土的晶层间距得到扩充,粘土层间插入了高分子。纳米复合材料具有与用炭黑补强的材料同样的良好性能。     

粘土的化学组成对天然橡胶／粘土复合材料性能的影响

用超声波和离心分级方法将3种来源不同的粘土进行分级,通过电子探针、红外光谱、X-射线衍射研究了各级份粘土的晶体结构、金属氢化物及粒子表面基团,并对相应级份的粘土胶进行物理力学性能测试。结果表明,粘土中的铁、铜、锰、钴、铬等化学组分含量对粘土胶的性能未产生积极影响,而粘土粒子表面羟基基团数量对粘土的补强性能起着显著作用。     

聚乙烯醇/粘土复合凝胶的制备及性能

文章采用冷冻-解冻法和硼酸法完成了聚乙烯醇包埋粘土微球复合材料的制备,进行了复合凝胶的力学性能和溶胀特性的测试,研究比较了不同的制备方法对复合凝胶的影响。结果表明冷冻-解冻法制备的PVA凝胶比硼酸法制备的PVA凝胶承受的拉升强度更大可以达到3.29MPa,添加粘土后的复合凝胶的溶胀性能减弱到原来的一半。