三甲基戊二醇的合成及应用研究

采用异丁醛缩合、交叉Cannizzaro反应制备了三甲基戊二醇(TMPD),并利用TMPD合成两种具有重要用途的新型香精青叶恶烷和环状碳酸酯IDDO.简要介绍了这两种合成香精在食品工业中的应用.     

青叶噁烷合成新工艺

本文通过异丁醛的自身缩合、交叉坎尼扎罗反应制备及2,4-三甲基-1,3-戊二醇（简称为TMPD）,然后利用TMPD和异丁醛的关环反应合成了青叶■烷,该方法操作简便,条件温和、产率较高。     

对甲苯磺酸催化合成青叶噁烷

文章考察了以对甲苯磺酸为催化剂、异丁醛和2,2,4-三甲基-1,3-戊二醇（TMPD）为原料催化合成青叶噁烷,实验结果表明对甲苯磺酸对青叶噁烷的合成效果极好;并进一步考察催化剂用量、醛与醇摩尔比、反应时间,反应温度对合成青叶噁烷反应的影响.合成青叶噁烷适宜的条件为：n（异丁醛）：n（TMPD）=2：1,催化剂0.2 g,反应时间2.5 h,反应温度115～120℃.在此条件下,TMPD的转化率达到94.4％,青叶噁烷的选择性为99.8％.该催化剂与其他催化剂相比价格便宜,催化性能高,工艺条件简单易操作.     

低粘度水性聚氨酯预聚体

采用四甲基苯二甲基异氰酸酯（TMXDI）与自制的聚己二酸－2，2，4－三甲基－1，3－戊二醇（TMPD）酯二醇（简称自制TMPD聚酯二醇）为主要原料，合成了具有低粘度特性的预聚体，制得不含或含有少量有机溶剂的单组分水性聚氨酯分散体PUD。探讨了该预聚体的合成工艺路线。研究了不同聚酯对预聚体粘度的影响。     

高耐候性聚酯树脂的合成与研究

利用NPG、1,6-HDO、1,4-CHDM、TMPD、TMP、1,4-CHDA、HHPA、THPA等脂肪族、脂环族单体合成高耐侯聚酯树脂,通过分步合成法与一步合成法的对比,显示分步合成法合成的高耐候聚酯具有更好的综合性能.     

三甲基戊二醇制备与应用研究进展

1 概况 三甲基戊二醇,学名2,2,4-三甲基-1,3-戊二醇(TMPD),是近30年发展起来的一种具有潜在用途的有机化工中间体。通常条件下TMPD呈白色片状晶体,但由于其熔点较低(51℃),因而适于在熔化状态下进行操作处理。TMPD易溶于大多数醇、芳香烃、酮、醚,微溶于脂肪烃、卤代烷烃及水。     

肉桂酸苄酯合成的新方法

肉桂酸苄酯合成的新方法孟菁＊谢筱娟方百盈郑爱华（安徽师范大学化学系,芜湖２４１０００）肉桂酸苄酯是一种无色固体香料,具有凤仙花香味,主要用于配制皂用香精、化妆香精及果酱香精等日化和食品工业中［１］。文献［２］报道的经典合成方法是使用肉桂酸钠和氯代苄为...     

新铃兰醛香料的合成

<正> 新铃兰醛(Lyral)是调配香精常用的香料,同时也是产量较大的合成香料之一。一般是两种异构体的混合物,结构式如下:     

芳樟醇的合成

前言芳樟醇(3,7-二甲基-1,6-辛二烯-3-醇)是一种名贵的香料,具有浓郁的香味。芳樟醇及其酯类广泛应用于配制花香型香精,少量用于食用香精中,同时又是合成维生素E的重要中间体。芳樟醇的合成有全合成法及半合成法。     

百润股份:产品高附加值长期稳定发展

近年来香精行业稳定发展香精行业主要以天然香料和合成香料为原料,其下游则涉及到食用香精、烟用香精、日用香精等领域。由于几个下游均为消费领域,其需求平稳,因此香精行业近年也呈现典型的稳定发展趋势。     

Catalytic action of metal salts in autoxidation and polymerization. X. The effect of various metal stearates on the thermal oxidation of 2,6,10,14-tetramethylpentadecane

The various metal stearate-catalyzed thermal oxidations of 2,6,10,14,-tetramethylpentadecane (TMPD, a model compound of polypropylene) and the decomposition of TMPD hydroperoxide (TMPD-HPO) were carried out. The results obtained were compared with those of the oxidation of polypropylene reported previously;¹⁸ and the initial tion process of the oxidation of the polymer is discussed. The catalytic activity of metastearates in the oxidation of polypropylene differed from that in the oxidation of pure TMPD and was fairly similar to that in the oxidation of TMPD with TMPD-HPO. The more effective the catalyst for the decomposition of TMPD-HPO, the more effective it was for the oxidation of both TMPD with TMPD-HPO and polypropylene. The results apparently indicate that metal catalysts enhance the decomposition of hydroperoxides which presumably contaminate the polymer and form during the oxidation, and also imply that the initiation of the oxidation of polypropylene is primarily affected by the presence of hydroperoxide contamination of the polymer.     

Regioselective Alkoxylation of 2,2,4-Trimethyl-1,3-pentanediol

An efficient procedure for the regioselective synthesis of secondary alcohol alkoxylates from 2,2,4-trimethyl-1,3-pentanediol (TMPD) is described. TMPD was reacted with propylene oxide followed by ethylene oxide in the presence of a catalytic amount of alkali metal hydroxide to form secondary alcohol alkoxylates. Instead of a mixture of compounds resulting from the reaction of TMPD and propylene oxide, the primary hydroxyl group of the TMPD reacted to form predominantly 2,2,4-trimethyl-3-hydroxypentylpropoxylate as the major product. On further ethoxylation the less hindered secondary hydroxyl group of the 2,2,4-trimethyl-3-hydroxypentylpropoxylate reacted predominantly. ¹³C NMR indicated that the secondary hydroxyl group (96.2 mol%) of TMPD remained unreacted during alkoxylation.     

HY沸石分子筛催化合成青叶(噁)烷

研究了以异丁醛和2,2,4-三甲基-1,3-戊二醇(TMPD)为原料,HY沸石分子筛为催化剂合成了青叶口恶烷的反应,考察了醛醇比、反应时间、带水剂、催化剂用量与其循环使用性对该反应的影响。结果表明:与传统催化体系相比,该体系不仅具有相当的转化率和选择性,而且具有催化剂分离简单、可循环使用的优点。     

N,N,N′,N′-对四甲基苯二胺光致电子转移变色体系的研究

研究了由N,N,N′,N′-对四甲基苯二胺(TMPD)/电子受体组成的光致电子转移变色体系,及其在溶液中和高分子膜中的光反应和热稳定性。实验结果表明这类光致变色体系具有较高速度的光响应能力。在不同芳胺/碘鎓盐(DPIOC)组成的体系中,可观察到电子转移速度随芳胺的氧化还原电位下降而增加:TMPD>N,N-二甲基苯胺>三苯胺>二苯胺。光反应速度和反应物浓度具有一定指数关系,分别为0.66(TMPD)和0.16(二苯基碘铕盐)。在TMPD/卤代烃(RX)组成的体系中,发现卤代烃的C—X键较弱时,体系的光致生色反应速度较快。显然,这是由于反应中间产物(RX~-)的分解有利于减少电子逆转移反应的缘故。在聚甲基丙烯酸甲酯高分子膜中的光致生色反应效率显著地高于溶液中的反应效率,并能获得较高的光密度。热稳定性结果表明,温度对色稳定性有显著影响,每经过一次生色/褪色循环,体系的发色能力下降一半左右。     

Trimethylpentanediol dibenzoate: New plasticizer for plastisol screen ink

Trimethylpentane diol (TMPD) dibenzoate use in vinyl as a plasticizer is not well recognized, and little has been published on vinyl performance characteristics. To assess new applications for vinyl, a basic evaluation was conducted. Based on the results of the screen and other considerations an evaluation for utility in plastisol silk screen ink was conducted. The results indicated that the TMPD dibenzoate performed very well in white ink, requiring good fabric dye bleed resistance compared to polymeric and phthalates currently being used for non-bleed ink. Non-bleed characteristics are important for colored tee shirt printing. The benzoate is a good solvator and has excellent extraction resistance.     

Photodegradation of Poly(L‐lactic acid): Effects of Photosensitizer

Summary: Amorphous and crystallized poly(L ‐lactic acid) (PLLA‐A and PLLA‐C, respectively) films with different contents of N,N,N′,N′‐tetramethyl‐1,4‐phenylenediamine (TMPD) as a photosensitizer were prepared, and the effects of the addition of TMPD on the photodegradation of PLLA films were investigated. It was found that the addition of TMPD effectively enhanced the photodegradation of PLLA films and thereby decreased their molecular weight of PLLA films regardless of their crystallinity, and that PLLA films with different molecular weights can be prepared by the addition of different amounts of TMPD and subsequent UV irradiation. Too high contents of TMPD however caused the brittleness of PLLA films due to a large decrease in molecular weight. The PLLA chains in crystalline regions as well as those in amorphous regions are photodegradable even at an early stage, in marked contrast to their hydrolytic degradation, where the chains in the amorphous regions are selectively degraded. The basic changes in glass transition, cold crystallization, and melting temperatures (T_g, T_cc, and T_m, respectively) of PLLA films during UV irradiation can be ascribed to low‐temperature annealing effects; i.e., annealing‐induced stabilization in chain packing should have elevated T_g, and annealing‐induced formation of crystallite nuclei should have lowered T_cc and increased T_m. The exceptional large decreases in T_cc and T_m of UV‐irradiated PLLA‐A films and in T_g of UV‐irradiated PLLA‐C films at high TMPD contents are attributable to the large decrease in molecular weight, whereas the exceptional decrease in T_m of PLLA‐C films at high TMPD contents can be due to the folding surface structural change of crystalline regions or to the lattice disorder caused by molecular structural changes.

of PLLA‐A films before UV irradiation and after UV irradiation for 60 h as a function of TMPD content.     

醇酸缩聚反应温度对反应级数的影响

当非等物质的量比n(醇)：n(酸)=1．1：1时、自催化的己二酸／新戊二醇、己二酸／2，2，4-三甲基-1，3-戊二醇缩聚反应级数不是定值，而是与反应温度有关。低温时反应级数为2．5，高温时反应级数为3．0。     

Synthesis and self-assembly of polyimide/poly(dimethylsiloxane) brush triblock copolymers

A series of novel brush triblock copolymers containing ‘glassy’ fluorinated polyimide, poly((4,4′-hexafluoroisopropylidene diphthalic anhydride)-co-(2,3,5,6-tetramethyl-1,4-phenylenediamine)) (poly(6FDA-co-TMPD)), and ‘rubbery’ polydimethylsiloxane monomethacrylate (PDMS-MA) were synthesized and characterized. Well-defined difunctional poly(6FDA-co-TMPD) with α,ω-amino end-groups was initially prepared via step-growth polymerization using precise control of the diamine (TMPD) to dianhydride (6FDA) ratio. Subsequent functionalization with 2-bromoisobutyryl bromide afforded a telechelic macroinitiator suitable for atom transfer radical polymerization (ATRP). The macroinitiator and its diamino poly(6FDA-co-TMPD) precursor were characterized via gel permeation chromatography (GPC), ¹H nuclear magnetic resonance (NMR) spectroscopic analysis and matrix assisted laser desorption ionization time-of-flight (MALDI ToF) mass spectroscopy. ATRP of PDMS-MA using the macroinitiator in different molar ratios afforded a series of brush triblock copolymers with high monomer conversions (88–94%) and varying PDMS weight fractions. Self-assembly of the triblock brush copolymers in dimethylformamide (DMF) afforded nanoparticles with hydrodynamic diameters (d_H) ranging from 87 to 109 nm, as determined by dynamic light scattering (DLS) analysis. Cross-linking of the nanoparticles was achieved via hydrogen abstraction through the thermal degradation of benzoyl peroxide. Transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) revealed that the self-assemblies and their cross-linked derivatives had spherical morphologies.     

Properties of a poly(acrylamide‐co‐diallyl dimethyl ammonium chloride) hydrogel synthesized in a water–ionic liquid binary system

A novel copolymer hydrogel, poly(acrylamide‐co‐diallyl dimethyl ammonium chloride), was prepared by the radical copolymerization of acrylamide and diallyl dimethyl ammonium chloride in an ionic liquid (IL)–water binary system in the presence of the crosslinker N,N′‐methylene bisacrylamide. The equilibrium swelling ratios of the hydrogels synthesized in the IL–water binary system increased with the content of IL and were remarkably higher than that of the gel synthesized in water. Differential scanning calorimetry measurements showed that the glass‐transition temperatures of the dry hydrogels that were synthesized in the IL–water binary system were remarkably lower than that of the gel synthesized in pure water. The mechanical properties of the gels synthesized in both water and the IL–water binary system were characterized with a universal material‐testing machine. The results show that fracture toughness of the hydrogels was improved when they were synthesized in the IL–water binary system. The gel shrank under a direct‐current electric field. The response rates of the gels that were synthesized with the IL–water binary system were faster than that of the gel synthesized in water. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010