PVC糊树脂交联改性新进展

1.引言作者“PVC 糊状树脂交联改性新方法”在《化学建材》1992.8(2):47～49发表以来,多位读者陆续询问,现推荐PVC 糊树脂交联改性的新方法,作为对读者的回答,并供有关读者参考应用。PVC 糊树脂加工容易,已在地板卷材、壁纸、人造革、其它室内装饰制品及电线电缆等领域广泛应用。近年来,人们对这些制品耐热性及耐火烫伤性的要求更加严格。为此,常采用交联改性提高其耐热软化性、耐烟火性及耐油性等。可是,在PVC糊状树脂中配合大量增塑剂往往延缓其交联速度。为了得到必要的交联度,需要在高温下长时间加热,结果变色严重。为了解决这种变色问题,常将可聚性增塑剂大量配合在PVC 中,在有机过氧化物自由     

PVC树脂取代剂在塑料壁纸中应用

PVC树脂取代剂是一种新型的化工原料,价格便宜,只占树脂价格的1/4。这种PVC 树脂取代剂在壁纸配方中取代部份树脂,具有很大的经济价值。     

阻燃PVC糊的粘度和凝胶化性能研究

阻燃PVC糊中,糊树脂类型及阻燃性组分对糊粘度影响显著。添加已二酸二辛酯、十二烷基苯可降低糊粘度,邻苯二甲酸丁苄酯可缩短凝胶化时间。     

PVC塑料地板胶粘剂的研制

叙述了用PVC 树脂配制PVC 塑料地板胶粘剂的配方、生产工艺等,介绍了产品的施工方法及产品性能。     

硬质PVC门窗异型材挤出技术的新发展

介绍硬质ＰＶＣ门窗异型材生产技术在物料处理自动化,共挤出技术,高速挤出技术,开发新型材及挤出模具设计制造中采用计算机技术等方面的发展趋势,采用新技术将提高异型材的质量,降低生产成本,增强市场竞争优势。     

Applicability of alkaline hydrolysis for remediation of TNT-contaminated water

This study was conducted to assess the applicability of alkaline hydrolysis as an alternative ex situ technology for remediating 2,4,6-trinitrotoluene (TNT)-contaminated water. TNT reactivity had a strong dependence on the reaction pH (11-12) and initial TNT (5-25 mg L(-1)) in batch systems, resulting in pseudo first-order transformation rate, k ranging between 1.9 x 10(-3) and 9.3 x 10(-5) min(-1). In continuous flow stirred-tank reactor (CFSTR) systems with initial TNT of 1 mg L(-1), the highest 74% of TNT reduction was achieved at the reaction pH of 11.9 and 2-day hydraulic retention time under steady-state condition. Oxalate was produced as the major hydrolysate in the CFSTRs, indicating a ring cleavage during alkaline hydrolysis. It was also believed that TNT alkaline hydrolysis occurred through the production of color-forming intermediates via dimerization. It is concluded that alkaline hydrolysis can be an alternative treatment technology for remediation of TNT-contaminated water.     

聚苯醚再分配产物改性环氧树脂的研究

利用聚苯醚(PPO)经再分配反应制得低分子量的聚苯醚再分配产物(REPPO),REPPO通过聚甲基三乙氧基硅烷(PTS)化学改性双酚A型环氧树脂。通过对REPPO的相对分子质量及分布的测定,表明了聚苯醚再分配产物的发生。通过对化学改性产物的红外光谱的测定,表明REPPO已成功引入环氧树脂。研究了REPPO含量对环氧树脂固化物力学性能和耐热性的影响。结果表明,经REPPO改性的环氧树脂的拉伸强度、断裂伸长率、玻璃化转变温度(Tg)以及热稳定性的影响有了明显的提高。     

Vero细胞形变表征污染物生物毒性的可靠性分析

考察了2,4,6-三氯苯酚（TCP）和饮用水相关材料（PVC管和一次性塑料水杯）的浸泡液致Vero细胞变形的灵敏度与相关性,并与四氮甲唑蓝（MTT）比色法进行了比较。结果表明：TCP对Vero细胞的毒性响应浓度为0．5mg／L,且变形细胞的比例与TCP浓度呈正相关,而MTT比色法测定低浓度TCP（〈1．0mg／L）致Vero细胞增殖抑制率的结果不稳定;流式细胞仪AN—NEXINV—FITC／PI双染色法的检测结果显示,细胞膜损伤是Vero细胞毒性的早期表现特征,比细胞凋亡和坏死更灵敏;Vero细胞暴露于饮用水相关材料的浸泡液时,其变形细胞的比例随浸泡温度的升高而增加,而在相同条件下,MTT比色法测定的浸泡液对Vero细胞的增殖抑制率则呈现不规律变化。     

Prediction of non-woven geotextiles’ reduction factors for damage caused by the drop of backfill materials

The need for sustainable solutions in geotechnical works has encouraged the investigation of recycled construction and demolition wastes (RCDW) as backfill material. The possible damages caused by the launching (dropping) process of this “new” backfill material (RCWD) must be quantified for its combined use with geosynthetics. This study evaluated the influence of the backfill's grain-size distribution and the geotextile's mass per unit area in the damages caused by the launch of RCDW material and aimed to provide a prediction equation of the reduction factors. Five RCDW materials were launched from 1.0-m and 2.0-m height over five non-woven polyester needle-punched geotextile and specimens were exhumed to be tested under tensile. Databases were created with the results and subjected to machine learning to obtain a prediction equation for the reduction factor's values. The results show that the damages caused by the dropping height are complex. The 1.0-m increase in the drop height and the increase in the geotextile's mass per unit area cannot be associated with an increase in the damage. The geotextiles were more affected by the backfills with uniform gradation. A reduction factor's prediction equation is presented considering the three variables investigated (geotextile, drop height and backfill material classification). The artificial neural network is a more interesting solution than multiple linear regression since it does not possess several application criteria and provides more accurate predictions.