亚磷酸酯类抗氧剂及其应用

亚磷酸酯是聚烯烃加工用辅助抗氧剂的主要品种之一,文章综述了亚磷酸酯类抗氧剂的作用机理、结构类型、品种开发及其在聚烯烃稳定化中的应用。     

红外光谱法定性和定量分析聚烯烃中微量抗氧剂168

研究了用红外光谱法快速测定（聚乙烯、聚丙烯）中微量亚磷酸酯类抗氧剂168的含量，确定了其与固体粉料的混合方式为溶剂混合；分析了抗氧剂168与PE、PP粉料共混的FTIR图，确定了抗氧剂168在PE、PP中的特征吸收峰分别为854cm^-1、1082cm^-1，详细分析了抗氧剂168分别与特定组成的PE、PP、主抗氧剂1010及硬脂酸钙所制样品对所测谱图和所制曲线的影响。根据抗氧剂168的标准曲线可知。抗氧剂168的含量与其特征峰的吸收强度呈良好的线性关系，相关系数达0．96以上，样品中抗氧荆168的回收率高于94．7％。该方法已用于快速定性和定量分析实际样品。     

亚磷酸三(2,4-二叔丁基苯基)酯的合成及其晶体结构

由2,4-二叔丁基酚与PCl3在二甲苯溶剂中反应合成了亚磷酸三(2,4-二叔丁基苯基)酯,其分子式为C42H63O3P.通过Nonius CAD4型X-射线衍射仪检测,其晶体结构测定结果如下:该晶体属于三斜晶系,P-1空间群,a=1.329 9(3)nm,b=1.350 3(3)nm,c=1.385 2(3)nm,α=112.20(3)°,β=104.66(3)°,γ=102.31(3)°,Dc=1.027 g/cm3,Z=2,F(000)=708,μ=0.098 mm-1,最终偏差因子分别为R=0.096 5,wR=0.245 0.X-射线衍射分析表明,分子内部分相邻原子间形成C—H…O氢键.     

纯棉用耐久阻燃剂KX-912的研制及应用

以亚磷酸二甲酯和丙烯酰胺为原料,合成了耐久阻燃剂KX-912,重点讨论了羟甲基甲醛和游离甲醛含量对反应的影响。通过实验,确定了反应的最佳原料配比、反应温度及催化剂用量。测得羟甲基甲醛含量接近9%,游离甲醛含量低于0.7%,收率达90%。     

Phosphorus induced hydrothermal stability and enhanced catalytic activity of ZSM-5 in methanol to DME conversion

The change in properties of ZSM-5 samples was achieved by treatment with phosphorus compounds (trimethyl phosphite or phosphoric acid) and the resultant materials were characterized by N₂ adsorption, NH₃-TPD, ²⁷Al, and ³¹P MAS NMR techniques. The phosphorus-treated HZSM-5 (P/ZSM-5) samples exhibited lower acidity, higher hydrothermal stability and improved dimethyl ether (DME) selectivity in methanol conversion when compared to the phosphorus-free HZSM-5. ²⁷Al, and ³¹P MAS NMR results revealed that the added P indeed interacted with the ZSM-5 framework and is responsible for the changes observed in the catalytic properties. The interaction caused the decrease in strong acid sites on one hand and creation of new acid sites (NH₃-TPD) on the other, in P/ZSM-5 samples. The studies indicated the need of optimizing the P loading, where the positive role of P on the catalytic activity was observed to be maximum at P/Al molar ratio of 1.05.     

Living polymerization of 1,3-butadiene by a Ziegler-Natta type catalyst composed of iron(III) 2-ethylhexanoate, triisobutylaluminum and diethyl phosphite

Living characteristics of facilely prepared Ziegler-Natta type catalyst system consisting of iron(III) 2-ethylhexanoate, triisobutylaluminum and diethyl phosphite have been found in the polymerization of 1,3-butadiene in hexane at 40 °C. The characteristics have been well demonstrated by: a first-order kinetics with respect to monomer conversion, a narrow molecular weight distribution (M_w/M_n = 1.48-1.52) of polybutadiene in the entire range of polymerization conversion and a good linearity between M_n and the yield of polymer. Feasible post-polymerization of 1,3-butadiene and block co-polymerization of 1,3-butadiene and isoprene further support the living natures of the catalyst bestowed with. The current catalyst system is highly active (yield > 80%, 35 min), providing polybutadiene with 1,2, cis-1,4 and trans-1,4 units about 44.0%, 51.0% and 5.0%, respectively.     

抗氧剂619的性能及其在聚丙烯中的应用

介绍了抗氧剂619的性能特点以及在聚丙烯中的应用效果,分析了在小本体聚丙烯中使用抗氧剂619作热、氧稳定刑的可能性。     

滴定法测定亚磷酸二甲酯含量的改进

本文采用三乙胺代替氢氧化钠浊寂亚磷酸二甲酯的酸度，碱解法测定亚磷酸二甲酯的含量。该法用于测定合成样品中亚磷酸二甲酯的含量和酸度，结果满意。     

Effect of Montmorillonite Clay on the Burning Rate of High-Impact Polystyrene

The effect that montmorillonite clay has on the burning rate of high impact polystyrene (HIPS) is examined. Two clays are considered a pristine montmorillonite (MMT-Na⁺) and a montmorillonite clay intercalated with triphenyl phosphite (TPP). In addition to the burning rate tests, mechanical, impact and rheological properties are determined. Results show an increase of 55% in the burning rate of the nanocomposite when the neat MMT-Na⁺ clay is added. Thermal measurements indicate a diminishing HIPS decomposition temperature as the MMT-Na⁺ clay concentration rises. On the other hand, when TPP is incorporated in MMT-Na⁺ (MMT-i-TPP) and the clay is added to HIPS, a substantial reduction (42%) of the burning rate is observed, while the mechanical properties are kept at the level of those of the original HIPS. The system HIPS-MMT-i-TPP presents a steeper reduction in the viscosity as compared to HIPS in the high-temperature range.     

亚磷酸三丙酯合成工艺研究

以三氯化磷和正丙醇为原料。采用直接反应的合成路线合成了亚磷酸三丙酯阻燃剂,并用FTIR、^1HNMR对产物进行表征。确定了最佳工艺条件：n（CH3CH2CH2OH）：n（PCl3）为3：1,PCl3滴加温度20～30℃;反应温度70℃;反应时间2h;收率61．8％。