亚磷酸三苯酯扩链制备PBT/PET合金

采用亚磷酸三苯酯(TPPi)作为扩链剂熔融共混制备了聚对苯二甲酸丁二醇酯(PBT)/聚对苯二甲酸乙二醇酯(PET)合金.通过力学性能测试、毛细管流变仪、差示扫描量热法(DSC)研究了TPPi的用量对PBT/PET体系力学性能、流变行为及结晶性能的影响.结果表明,加入TPPi后PBT/PET体系的拉伸强度提高至60MPa...     

New poly(amide–imide)s syntheses. 17. Preparation and properties of poly(amide–imide)s derived from N-phenyl-3,3-bis[4-(4-aminophenoxy)-phenyl]phthalimidine,trimellitic anhydride,and various aromatic diamines

A dicarboxylic acid ( 1 ) bearing two phthalimide rings was prepared by the condensation of N-phenyl-3,3-bis[4-(4-aminophenoxy)phenyl]phthalimidine and trimellitic anhydride. A new family of poly(amide–imide)s having inherent viscosities of 0.65–1.65 dl/g was prepared by the triphenyl phosphite activated polycondensation of the diimide–diacid 1 with various aromatic diamines in a medium consisting of N-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. All the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. The soluble poly(amide–imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range 249–340°C and the 10% weight loss temperatures were above 545°C in nitrogen.     

液体稳定剂中游离苯酚的测定

提出了一种测定液体稳定剂中的游离苯酚含量的化学分析方法。其原理基于苯酚能与溴定量反应。具体的步骤是,向液体稳定剂中加入定量的溴,用定量的碘化钾与溴化反应后剩余的溴反应,再用Na2S3O3标准溶液滴定反应生成的碘。根据Na2S3O3标准溶液用量,可以计算出液体稳定剂中游离苯酚的含量。     

Modular P?OP Ligands in Rhodium‐Mediated Asymmetric Hydrogenation: A Comparative Catalysis Study

Highly efficient and enantioselective hydrogenation reactions for α‐(acylamino)acrylates, itaconic acid derivatives and analogues, α‐substituted enol ester derivatives, and α‐arylenamides (25 substrates) catalyzed by chiral cationic rhodium complexes of a set of P OP ligands have been developed. The catalytic systems derived from these P OP ligands provided a straightforward access to enantiomerically enriched α‐amino acid, carboxylic acid, amine, and alcohol derivatives that are valuable chiral building blocks. Excellent efficiencies (full conversion in all cases) and extremely high enantiomeric excesses (94–99% ee) were achieved for a wide range of α‐substituted enol ester derivatives, regardless of the substitution pattern. The R‐oxy group of the ligand (methoxy or triphenylmethoxy) strongly influences the enantioselectivity and catalytic activity. Greater steric bulk around the metal centre correlated to greater (or similar) enantioselectivity, but also to slower hydrogenation. Furthermore, the hydrogenation rates observed with the four model substrates follow the same trend, independently of the R‐oxy group of the ligand: methyl 2‐acetamidoacrylate>dimethyl itaconate>1‐phenylvinyl acetate>N‐(1‐phenylvinyl)acetamide. A substrate‐to‐catalyst ratio (S/C) of up to 10,000:1 was sufficient for total hydrogenation of a model substrate of intermediate reactivity (dimethyl itaconate), and did not imply any loss in conversion or enantioselectivity.     

内环双酚亚磷酸酯类抗氧剂HP-10的合成研究

研究了以2,2′-亚甲基双(4,6-二叔丁基苯酚)(简称双酚Z)与三氯化磷为原料,经一级酯化反应生成2,2′-亚甲基双(4,6-二叔丁基苯基)亚磷酸酯一氯化物;与异辛醇二级酯化反应生成2,2′-亚甲基双(4,6-二叔丁基苯基)异辛烷氧基亚磷酸酯(简称HP-10)。一级酯化工艺条件:n(双酚Z)∶n(三氯化磷)=1.0∶1.3,催化剂0.2g,反应时间2.0h,温度85.0℃;二级酯化工艺条件:异辛醇6.5g,缚酸剂13.0g,反应时间4.0h,温度85.0℃。合成HP-10收率达84.3%,熔点147.5～148.2℃,经IR1、H NMR、13 C NMR、LC-MS谱图解析,与HP-10结构相符,产物质量分数大于97.0%。     

2-（二乙氧基磷酰基）-3-甲基丁酸乙酯的合成改进

以氯乙酸乙酯为原科与亚磷酸三乙酯经Arbuzov反应合成中间体2-（二乙氧基磷酰基）-乙酸乙酯,再与2-溴丙烷反应制备得到2-（二乙氧基磷酰基）-3-甲基丁酸乙酯.两步总收率79.1％.     

常减压装置环烷酸腐蚀的缓蚀剂研究

由于稠油中的环烷酸对常减压装置有较强的腐蚀作用而必须进行防护。选择咪唑啉和亚磷酸二乙酯两种环烷酸的缓蚀剂进行复配。采用静态失重法在常温和高温(280℃)下对缓蚀剂进行性能评价。实验结果表明:常温下亚磷酸二乙酯的含量越大,缓蚀剂对试件的腐蚀性就越严重。高温下,在咪唑啉和亚磷酸二乙酯2∶1配比时,缓蚀剂的加入量为0.1%时缓蚀效率最大,缓蚀率为91.55%。     

抗氧剂168的降解及其降解产物的测定

抗氧剂168标准品及将其添加到聚丙烯薄膜中,经过紫外或微波处理均会发生降解,产生降解产物。以正己烷为提取溶剂,建立了聚丙烯薄膜中抗氧剂168及其降解产物2,4-二叔丁基苯酚和三(2,4-二-叔丁基苯基)磷酸酯的气相色谱-质谱检测方法。结果表明:三种物质分别在25~150 mg/L,0.02~20 mg/L,0.05~10 mg/L的浓度范围内线性关系良好,R~2分别为0.9990、0.9989、0.9955,回收率在81.83~115.21%之间,RSD在0.10~4.54%之间,检出限(LOD)分别为5.00μg/L,0.20μg/L和25.00μg/L,定量限(LOQ)分别为12.00μg/L,0.45μg/L和60.00μg/L,可见该方法精密度好,灵敏度高,定性定量准确,可用于聚丙烯中抗氧剂168及其两种降解产物的检测。将抗氧剂168添加到聚丙烯中经紫外、微波处理,降解率分别为31.88%、11.79%,产生3个降解产物,由标品确定其中两个为2,4-二叔丁基苯酚和三(2,4-二-叔丁基苯基)磷酸酯,推测另一个为抗氧剂168失去一个双叔丁基苯酚的产物;抗氧剂168标准品经紫外或微波处理,降解率均在5%以下。     

复合型受阻酚抗氧剂的制备及清除DPPH·活性研究

以二苯基氯化磷和2,2′亚甲基双(4甲基6叔丁基苯酚)为原料,合成具有亚磷酸酯及受阻酚结构的复合型抗氧剂2(2羟基3叔丁基5甲基苄基)4甲基6叔丁基苯基二苯基亚磷酸酯,产率为65.12 %,产物经FT-IR表征,符合理论设计构型。将产物与商用抗氧剂2,6二叔丁基4甲基苯酚(BHT)进行热稳定性及DPPH自由基清除能力的对比测试,结果表明,产物较抗氧剂BHT分子量更高,热稳定性更好;同时其对DPPH自由基具有良好的清除效果,其抗氧化能力强于抗氧剂BHT。     

Modular Synthesis of Chiral Phosphine‐Phosphite‐Ligands from Phenolic Precursors: A New Approach to Bidentate Chelate Ligands Exploiting a P?O to P?C Migration Rearrangement

An efficient and modular approach to bidentate phosphine‐phosphite ligands formally derived from a 6‐alkyl‐2‐phosphanylphenol, a chiral diol and phosphorus trichloride has been developed. In a key step, a borane‐protected phosphinite, prepared from an o‐bromophenol by O‐phosphanylation, is reacted with n‐butyllithium to afford the corresponding ortho‐phosphanylphenol (as the stable borane adduct) through bromine‐lithium exchange and anionic migration rearrangement. Treatment with phosphorus trichloride in the presence of a base and subsequent reaction of the in situ formed dichlorophosphite with a chiral diol (such as TADDOL or BINOL) affords the target P,P ligands in good overall yield (up to 60% over 4 steps). In contrast to an earlier approach, the new methodology is very general and tolerates bulky ortho‐substituents. The reliability of the operationally convenient protocol was demonstrated in the synthesis of a library of 16 new phosphine‐phosphite ligands, starting from different ortho‐alkylphenols. The modular concept opens a rapid access to a broad variety of ligands and might be useful in the search for and structural optimization of suitable ligands for specific chirogenic transition metal‐catalyzed transformations.