Salen Mn(Ⅲ)/NBS催化次氯酸钠氧化4,4'-二羟基二环己烷合成4,4'-二环己酮

以Salen-Mn(Ⅲ)为催化剂、NBS为溴源构建了一种催化体系,以次氯酸钠为氧化剂成功地将4,4'-二羟基二环己烷氧化为4,4'-二环己酮。分别考察了催化剂Salen Mn(Ⅲ)、NBS以及次氯酸钠用量对反应的影响,发现当4,4'-二羟基二环己烷为0.5 mmol、Salen-Mn(Ⅲ)为0.04 mmol、NBS为0.26 mmol、次氯酸钠为18 mmol时,在25℃反应0.5 h,4,4'-二羟基二环己烷的转化率和4,4'-二环己酮的选择性分别高达96.1%和93.0%。     

含羟基聚酰亚胺改性环氧胶的制备及性能研究

将3,3'-二氨基-4,4'-二羟基联苯(DADHBP)、2,2-双(3-氨基-4-羟基苯基)六氟丙烷(BAH-PFP)和3,3',4,4'-四羧酸二苯醚二酐(ODPA)、3,3',4,4'-四羧酸二苯甲酮二酐(BTDA)单体聚合,再经亚胺化得到含羟基聚酰亚胺(HPI)粉末,采用傅里叶红外光谱对其进行了表征。由HPI、烯丙基双酚A、双马来酰亚胺、2-乙基-4-甲基咪唑与N,N,N',N'-四缩水甘油基-4,4'-二氨基二苯甲烷(TGDDM)共聚反应制得胶粘剂,并对胶粘剂的热性能、力学性能及吸水性进行了研究,结果表明:该胶拉伸剪切强度为21.1 MPa,固化后吸水率为0.49%。通过凝胶化时间法计算胶粘剂的表观活化能为64.5 kJ/mol。     

比沙可啶的合成工艺研究

以2-吡啶甲醛为起始原料,在浓硫酸催化下,与苯酚缩合得到4,4'-二羟基二苯基-(2-吡啶)-甲烷和2,4'-二羟基二苯基-(2-吡啶)-甲烷,利用二者在乙酸乙酯中溶解度的差别,分离得到4,4'-二羟基二苯基-(2-吡啶)-甲烷,用氢氧化钠转变得到酚钠盐后,经乙酰化得到比沙可啶。其结构经核磁共振氢谱确证,纯度经液相色谱分析为99%。改进后的合成工艺操作简便,收率可达58%。     

聚氨酯弹性体改性双马来酰亚胺树脂的研究

本文研究了聚醚-甲苯二异氰酸酯(TDI)对4,4'-二苯甲烷一双马来酰亚胺(BMI)/3,3'-二氯-4,4'-二胺基二苯基甲烷(MOCA)的增韧作用.内容包括:聚醚-TDI的含量对固化树脂力学性能、热性能的影响,分析了改性BMI/MOCA体系的固化反应机理,研究了MOCA扩链BMI的配方、反应性,确定了聚醚-TDI对BMI/MOCA树脂的改性配方及固化工艺.     

4-羟基-4''''-苄氧基二苯基砜的相转移催化合成研究

在相转移催化剂存在下.以4,4'-二羟基二苯基砜、氯化苄为原料合成4-羟基-4'-苄氧基二苯基砜,分别研究了反应温度、反应时间、原料配比、催化剂用量、溶剂用量等条件对合成反应的影响。确定了最佳工艺条件:反应温度80℃:反应时间5小时:N(4.4'羟基二苯基砜):N(氯化苄)=1:1.35:N(4.4'羟基二苯基砜):N(氢氧化钠)=1:1.1:催化剂用量为0.5％(相对于4,4'-二羟基二苯基砜的质量分数);产品收率:85.55％:产品纯度:98.50％。     

龙血竭黄酮类成分研究

为了解龙血竭中主成分(黄酮类化合物)的化学组成,通过碱溶酸沉初步提取,聚酰胺柱层析、硅胶柱层析和高效液相色谱对龙血竭进一步分离,借助波谱分析手段对分离出的化合物结构进行鉴定。共分离得11个黄酮类成分,其结构分别为:7-羟基黄酮(1),5,7,4'-三羟基-8-甲基黄酮(2),5,7,4'-三羟基黄酮(3),2,4'-二羟基-4,6-二甲氧基二氢查尔酮(4),2,4,4'-三羟基-6-甲氧基二氢查尔酮(5),4,4'-二羟基-2-甲氧基二氢查尔酮(6),4-羟基-2,4'-二甲氧基二氢查尔酮(7),7-羟基-4'-甲氧基黄烷(8),7,4'-二羟基-5-甲氧基高异黄烷(9),7,4'-二羟基-6-甲氧基高异黄烷(10),7,4'-二羟基高异黄烷(11)。     

3,3'-二氨基-4,4'-二羟基二苯砜的合成

3,3'-二硝基-4,4'-二氯二苯砜与氢氧化钠在二甲基亚砜中85℃反应得到3,3'-二硝基-4,4'-二羟基二苯砜,再经铁粉/氯化铵50℃下经还原反应得到3,3'-二氨基-4,4'-二羟基二苯砜,总收率74%。该路线具有收率高,原材料易得,环境友好等优点。     

3-(4’-羟基苯)硫酚醛环氧树脂的合成

以4,4'-二羟基二苯硫醚、甲醛为原料,经酚醛缩合合成了3-(4’-羟基苯)硫酚醛树脂,再与环氧氯丙烷聚合,制备了一种具备自阻燃性能的树脂3-(4’-羟基苯)硫酚醛环氧树脂,测定了环氧树脂产物的IR、TGA、阻燃性能。     

DGEBP液晶环氧树脂的合成研究

以4,4'-二-羟基联苯、环氧氯丙烷及异丙醇为原料,合成了联苯型刚棒状介晶结构的4,4'-二羟基联苯二缩水甘油醚(DGEBP)。采用红外光谱(FT-IR)、核磁共振仪(NMR)对DGEBP的分子结构和液晶性能进行表征,然后将该联苯类液晶与环氧树脂共混制备液晶/环氧树脂复合材料,采用带加热台的偏光显微镜(PLM)及差热扫描量热仪(DSC)等仪器对环氧树脂复合材料进行分析测试,结果表明实验合成出了一种低分子液晶环氧化合物。     

4,4''''-二氨基二苯胺-2-磺酸型黑色直接染料的合成

报道了以4,4'-酸(4,4'-二氨基-二苯胺-2-磺酸)代替联苯胺,与H酸(1-羟基-8-氨基-3,6-二萘磺酸)、间苯二胺、苯胺等合成无致癌作用的环保型黑色直接染料。探索了合成工艺及反应条件,并对其应用性能进行测试。合成的染料在溶解度、耐酸、耐碱棉织物的牢度性能和上染率等方面与商品染料基本相当。     

烯丙基酚醛改性双马来酰亚胺树脂的制备与性能

合成并表征了烯丙基酚醛树脂,再将其与双马来酰亚胺共聚制备了烯丙基酚醛改性双马树脂。通过DSC和FTIR分析了该树脂的固化行为,研究了其工艺性,利用TGA和DMA评价了其固化物的耐热性。结果表明,烯丙基酚醛树脂改性双马树脂可用于RTM等成型工艺,其固化物Tg约为330℃,初始热分解温度约400℃,5%失重温度达410℃,10%失重温度423℃。该树脂耐热性优异,可用作耐高温先进复合材料的基体树脂。     

低温固化改性BMI树脂基体动力学研究

采用催化剂、3,3′-二烯丙基双酚A(DP)和多官能团单体C改性4,4′-二氨基二苯甲烷双马来酰亚胺(BMI)树脂,制取低温固化、高温性能优良的改性BMI树脂。采用差示扫描量热法(DSC)研究了改性BMI树脂的固化反应动力学,计算了固化反应体系的动力学参数,进而提出了该改性BMI树脂固化成型过程的动力学模型,并结合傅里叶红外光谱(FT-IR)对反应机理进行了探讨。研究结果表明,催化剂对固化反应的进行有重要的促进作用,改性BMI树脂的固化温度由259℃降为178℃;烯丙基与马来酰亚胺基的"ene"反应非常显著,且改性剂C与DP的"ene"反应历程相似;改性BMI树脂的固化工艺确定为120℃×6h+140℃×2h+160℃×2h+180℃×2h,后处理工艺为200℃×6h。     

含氰基二元芳胺固化的酞菁预聚物的合成及表征

以亲核取代反应合成了3种酞菁单体(2,2′-二[4-(3,4-二氰基苯氧基)]丙烷(BAPh)、4,4′-二(3,4-二氰基苯氧基)联苯(BPh)、4,4′-二(3,4-二氰基苯氧基)甲烷(BFPh))和1种含有氰基的高熔点二元芳胺2,6-二(4-氨基苯氧基)苯甲腈(APBN)。通过核磁共振氢谱(1H-NMR)、傅里叶变换红外光谱(FT-IR)、示差扫描量热仪(DSC)和热重分析(TGA)对合成的化合物的化学结构,芳胺和酞菁单体的热聚合行为,不同固化时间预聚物的热性能进行了研究。结果表明,BAPh/APBN和BFPh/APBN体系分别具有宽达101℃与107℃的加工窗口。BFPh型预聚物(固化1 h)比其他2种预聚物具有更高的初始分解温度(390℃下失重5%)、高温残炭率(800℃下61.7%)和固化效率。     

Preparation and properties of bismaleimide resins of aromatic sulfone ether diamine

Aromatic sulfone ether diamine, bis[4-(4-aminophenoxy)phenyl]-sulfone (SED), was prepared by the nucleophilic aromatic substitution of 4,4′-dichlorodiphenylsulphone by p-aminophenolate. The reaction was conducted in the presence of excess potassium carbonate as a weak base, toluene as the dehydrating agent and N-methylpyrrolidone as the dipolar aprotic solvent. SED showed good solubility in common organic solvents, such as dioxan, tetrahydrofuran, butanone and acetone. SED was reacted with maleic anhydride to obtain aromatic sulfone ether bismaleimide, bis[4-(4-maleimidophenoxy)phenyl]-sulfone (SEM). The compounds were characterized by FTIR and ¹H NMR analysis. Furthermore, copolymer resins of SED with 4,4′-bismaleimidodiphenyl methane (BMI) and SEM were prepared. After curing, crosslinked resins with better thermal stability resulted. The temperature at maximum rate of weight loss (T_max) and the heat-resistant temperature index (T_i) in air were found to be 426°C, 208°C and 579°C, 221°C for BMI/SED and SEM/SED resins, respectively. Compared with the corresponding 4,4′-diaminodiphenyl methane (DDM) system, BMI/SED and SEM/SED showed a slight decrease in T_max and T_i SED-modified BMI/amine resin based glass cloth laminates for printed circuit boards showed higher mechanical properties than those of the corresponding unmodified system. With SED instead of the original amine component in 3–5% weight fraction, the tensile strength, flexural strength and impact strength of the laminates increased markedly. Meanwhile, the stripping strength and weld resistance were also improved by the addition of SED.     

二烯丙基双酚A改性双马来酰亚胺三嗪树脂的固化工艺及性能

以烯丙基化合物改性的方法制得了改性双马来酰亚胺三嗪(BT)树脂,研究了改性BT树脂体系的固化动力学,求得表观活化能为45.9 kJ/mol,反应级数为0.842,确定了固化工艺,并采用力学性能分析和动态热机械分析等手段对树脂浇铸体的性能进行了研究.结果表明,对于烯丙基化合物改性BT树脂体系,二烯丙基双酚A具有改善双马来...     

Fluorinated bismaleimide resin with good processability,high toughness,and outstanding dielectric properties

In this study, novel fluorinated bismaleimide (BMI) resins were prepared by the copolymerization of 2,2′‐bis[4‐(4‐maleimidephenoxy)phenyl]hexafluoropropane (6FBMP) and diallyl hexafluorobisphenol A (6FDABPA) to enhance their dielectric properties. The dielectric properties of the resins were investigated in the frequency range 7–18 GHz through a cavity method. Through the incorporation of a hexafluoroisopropyl group with the polymer chain, the dielectric constant (ε) was effectively decreased because of the small dipole and the low polarizability of the carbon‐fluorine (C? F) bonds. The 6FBMP/6FDABPA resin possessed excellent dielectric properties, with ε being 2.88 and the dielectric loss being 0.009 at 10 GHz and 25°C. In comparison with the 4,4′‐bismaleimidodiphenylmethane (BDM)/2,2′‐diallyl bisphenol A (DABPA) resin, the glass‐transition temperature (T_g) of 6FBMP/6FDABPA decreased. The flexible ether group in the long chain of 6FBMP was considered to disrupt chain packing and cause a decreased crosslinking density and a lower T_g. 6FBMP/6FDABPA showed a similar thermal decomposition temperature and good thermal properties like the BDM/DABPA resin, whereas the impact strength of the 6FBMP/6FDABPA resin was almost 1.6 times higher than that of the BDM/DABPA resin. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42791.     

Glass transition temperatures in bismaleimide-based resin systems

The glass transition temperatures in bismaleimide-based resins were investigated using different stoichiometric ratios of 1, 1′-(methylenedi-4, 1-phenylene)bismaleimide (BMI) and 4, 4′-methylenedianiline (MDA). The resin cure involves a low temperature primary amine addition to the maleimide double bonds and a high temperature homopolymerization of the maleimide double bonds. The network topology and the glass transition temperature changes with resin composition and curing conditions were determined using differential scanning calorimetry (DSC). An empirical model was used to relate the glass transition temperature to the extents of the amine addition and the homopolymerization reactions in 1:1 and 2:1 BMI:MDA resins. The changes in thermal properties with resin post-cure were also examined.     

High-refractive index polythiourethane resin based on 2,3-bis((2-mercaptoethyl) thio)-1-propanethiol and 1,3-bis(isocyanantomethyl) cyclohexane using tertiary amine catalyst

High-refractive index (RI) polythiourethane (PTU) resin with good thermal, optical, and mechanical properties was synthesized via thiol-isocynanate click reaction of 2,3-bis((2-mercaptoethyl)thio)-1-propanethiol and 1,3-bis(isocyanantomethyl) cyclohexane using a new tertiary amine catalyst N,N,N′,N′-tetramethyl-1,4-diaminobutane (TMDB). Curing behavior of PTU resin was studied by dynamic differential scanning calorimetry (DSC) technique. Curing technology parameters were optimized by combined use of DSC and fourier transform infrared spectrometry (FTIR). The results indicate that TMDB exhibits higher catalytic activity than commonly used dibutyltin dichloride (DBTC). The Kissinger apparent activation energies at a dosage of 150 ppm TMDB and 150 ppm DBTC are 31.7 and 43.2 kJ mol⁻¹, respectively. PTU resin with a full conversion of thiol and isocynanate was prepared, which exhibited better thermal, optical, and mechanical properties than that reported previously. The resin displays a glass transition temperature of 102 and 129°C determined by DSC and dynamic thermomechanical analysis (DMA), respectively, a 5% weight loss temperature of 279°C in nitrogen, a light transmittance of 87% in the wavelength range of 410–900 nm, a water contact angle of 100°, a high-RI of 1.617, and an Abbe number of 38. The resin was successfully applied in ophthalmic lenses.     

DDS固化EP/MMT纳米复合材料性能研究

以4,4′-二氨基二苯砜(DDS)为固化剂,制备出一种剥离型MMT/EP(蒙脱土/环氧树脂)纳米复合材料。采用红外光谱(FT-IR)法、X射线衍射(XRD)法和动态力学分析(DMA)法等对复合材料的微观结构、插层剥离行为、热性能和力学性能等进行了研究。结果表明:MMT对EP分子结构无影响,有利于EP结构和性能的设计,也便于确定其固化工艺。在无促进剂的情况下,当体系中引入5%MMT(相对于EP质量而言)时,复合材料的干态热变形温度、玻璃化转变温度(Tg)、冲击强度和拉伸强度分别提高了39℃、21℃、27.30%和10.50%;适量的MMT能有效提高纳米复合材料的耐湿热性能。     

汽车用耐高温结构胶的研制

以双组分环氧树脂(EP)为基体树脂、4,4′-二氨基二苯砜(DDS)改性双马来酰亚胺(BMI)为固化剂,采用共混法制备出一种汽车同步器用耐高温结构胶。采用差示扫描量热(DSC)法、热重分析(TGA)法和动态力学分析(DMA)法考察了不同固化工艺和不同配方对结构胶的粘接性能、耐热性能及耐冻融循环性能等影响。结果表明:当m(双组分EP)∶m(预聚体或固化剂)=1.0∶1.0以及采用阶梯升温固化工艺"150℃/1 h→180℃/2 h→200℃/1 h"时,该结构胶具有良好的粘接性能(用于碳纤维与金属间粘接时)和工艺性能,其室温剪切强度为33.9 MPa、180℃剪切强度为23.7 MPa;该结构胶可在低于180℃环境中长期使用,并完全满足汽车同步器的使用要求。