Synthesis and characterization of graft copolymers based on poly(p-phenylene terephthalamide) backbone and well-defined polystyrene side chains

<正>A novel dualfunctional monomer,2-(2',2',6',6'-tetramethyl-piperidinyl-1'-oxy)methylbenzene-1,4-dioyl chloride hydrochloride,with two acid chloride groups for step-growth polymerization and a nitroxide group for the mediation of living radical polymerization was synthesized.It was first copolymerized with terephthaloyl chloride and p-phenylenediamine at a feed molar ratio of 1:3:4 in N-methyl-2-pyrrolidone containing 10 wt%calcium chloride at -10℃to yield a poly(p-phenylene terephthalamide) based macroinitiator,which initiated radical polymerization of styrene at 125℃to obtain a series of poly(p-phenylene terephthalamide)-g-polystyrenes.A combinatory analysis of proton nuclear magnetic resonance spectroscopy,Fourier transform infrared spectroscopy,elementary analysis,thermogravimetry and gel permeation chromatography indicated that the macroinitiator induced the radical polymerization of styrene to proceed in a well-controlled way.The molecular weight of side-chains increased with an increase of monomer conversion,and the molecular weight distribution index remained lower than 1.5.The graft copolymers showed a remarkably improved solubility in N-methyl -2-pyrrolidone and much depressed crystallinity in bulk.     

Synthesis of 1-Bromo-3-methoxy-4-propoxy-5-iodobenzene——A Novel Efficient Process for the Synthesis of Brominated Aromatic Compound

The reaction of aromatic carboxylic acid with oxalyl chloride gives rise to the corresponding acid chloride which without purification is treated with the sodium salt of mercaptopyridine oxide in the presence of 2,2-azo-bisisobutyronitrile (AIBN), radical initiator to give a brominated aromatic compound. After etherification and oxidation, 5-iodovaniline was converted to trisubstituted benzene carboxylic acid which give 1-bromo-3-methoxy-4-propoxy-5-iodobenzene by this new brominating process with a yield of 74%.     

SYNTHESIS OF AN EPOXY-TERMINATED HYPERBRANCHED AROMATIC POLYESTER

An epoxy-terminated hyperbranched aromatic polyester (P3) was synthesized from a hyperbranched aromaticpolyester containing carboxylic acid end groups (P1), which was derived from the condensation polymerization of the AB_2monomer, 5-acetoxyisophthalic acid. Polymer P1 was converted into the polymeric acid chloride by reaction with thionylchloride. The acid chloride was reacted with ethanol and glycidol to form a poly(ethyl ester) (P2) and an epoxy terminatedmaterial (P3), respectively. The reaction conditions in each step of these processes had to be controlled very carefully toavoid unwanted cross-linking reactions. The characterization of products and intermediates, including molecular weightdistributions and thermal properties, are reported.     

Synthesis and characterization of benzocyclobuten-4-yl acrylate monomer and its radical polymerization

<正>A benzocyclobuten-4-yl acrylate(1) monomer was prepared by esterification of 4-hydroxybenzocyclobutene with acryloyl chloride.The radical homopolymerization of 1 and copolymerization of 1 with styrene or n-butyl acrylate were carried out to produce linear polymers 2a,2b and 2c.Heating of these linear polymers under thermal initiation gave corresponding cross-linked polymers 3a,3b and 3c.The ring-opening reaction in the cross-linking process was confirmed by on-line infrared spectra.Differential scanning calorimetry showed that the glass transition temperatures of linear polymers 2a and 2b were 83.2℃and 68.1℃,respectively.Thermogravimetric analysis of the cross-linked polymers showed that they all exhibited good thermal stability.     

Syntheses of 10-Hydroxy-5,10-dihydrophenophosphazine 10-Oxide and Its Methyl Derivatives

Ph2NH and PCl3 interacted at a molar ratio of 1:1.05 and slow-elevated temperature and then at 210-220 ℃ for 6h.The brown solution obtained was treated with H2O to produce a very hard brown solid believed to be a mixture of 5,10-dihydrophenophosphazine 10-oxide(1a) and 10,10′(5H,5H′）-spirobipenophosphazinium chloride(1b).This brown solid was directly oxidized with peracetic acid in HOAc prior to the separation of them to give compound 10-hydroxy-5,10-dihydropheno-phosphazine 10-oxide(2) with a higher yield(45%) than that of the literature(27%).When treated with excess SOCl2.compound 2 could quantitatively be converted to the corresponding phosphinyl chloride and the latter could further be transformed into 10-methoxy-5,10-dihydrophenophosphazine 10-oxide in 70% as treated with NaOMe in methanol.Compound 2 could also be converted to a bisanion when treated with NaH in DMF.The resulted bisanion reacted with MeI to give 5-methyl-10-hydroxy-5,10-dihydrophenophosphzine 10-oxide in a 73% yield which would be converted to 5-methyl-10-methoxy-5,10-dihydrophenophosphazine 10-oxide.All these compounds obtained were identified by surveying their melting points.and spectra and elemental analysis.     

Study on the Synthesis of Phenylacetic Acid by Carbonylation of Benzyl Chloride under Normal Pressure

The influences of some factors on the yield of phenylacetic acid in the carbonylation of benzyl chloride were studied in this paper. These factors included the variety and content of catalyst, and that of solvent, way of material feeding, reaction temperature, sodium hydrate concentration, triphenylphosphine content, presence of surfactant, the ratio of organic phase volume to aqueous phase volume etc. The optimum reaction conditions were found to be: with a one-time pour of 0.15g Pd(PPh3)2Cl2, 0.24g PPh3, 75ml NaOH of 3.5mol/L, 20ml benzyl chloride and 55ml n-butyl alcohol, and the reaction was carried out at 50℃ for about 3 hours. The as-obtained yield of phenylacetic acid was as high as 97.6%. In addition, the influences of the presence of phenylacetic acid and air in the reaction system were also studied. The results showed that the presence of air in the system and the entrainment of phenylacetic acid in the circulating organic phase had great influence on the reaction rate, the stability and performance of catalyst and the yield of phenylacetic acid.     

Thermal transformation of acid compounds in high TAN crude oil

The Liaohe crude oil with high total acid number (TAN) was subjected to thermal reaction at 300℃to 500℃. Reaction products were collected and analyzed by negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) to determine acid compounds in the crude oil. The double-bond equivalence (DBE) versus carbon number was used to characterize the oxygenated components in the feed and reaction products. The O2 class which mainly corresponds to naphthenic acids decarboxylated at 350-400℃, resulting in a sharply decrease in TAN. Phenols (O1 class) are more thermally stable than carboxylic acids. Carboxylic acids were also thermally cracked into smaller molecular size acids, evidenced by the presence of acetic acid, propanoic acid, and butyric acid in the liquid product. These small acid species are strong acids likely responsible for corrosion problems in refineries.     

A facile route for the syntheses of trisilanes containing C-mono-substituted carborane

The syntheses of trislanes containing C-monosubstituted o-carborane are described.Hie intermediate compound,2-chloro-2-phenyl-hexamethyltrisilane,was prepared by elimination reaction between 2,2-diphenylhexamethyltrisilane and hydrogen chloride with a catalytic amount of aluminum chloride in chloroform solution.     

SULFATION OF PACHYMAN WITH CHLOROSULFONIC ACID USING THE IMPROVED WOLFROM METHOD

High purity polysaccharide of pachyman was isolated from the powder of Poria cocos sclerotium with an yield of 77.8%. The intrinsic viscosity of polysaccharide was found to be 78.95 mL/g in DMSO solution at 25℃. The isolated polysaccharide was reacted with chlorosulfonic acid to obtain pachyman sulfate using the improved Wolfrom method. The results of the orthogonality experiment on the sulfation reaction identified that the effectiveness of the reaction conditions on the degree of sulfation and the value of intrinsic viscosity is in the following order: molar ratio of chlorosulfonic acid to glucoside (3-5) ＞ reaction temperature (60-80℃) ＞ reaction time (1-2 h). The kinetic studies of the pachyman sulfationindicated that the hydrolysis is accompanied with the sulfation process. The decrease in intrinsic viscosity of the sulfated pachyman is proportional to the increase in the degree of sulfation under the mild reaction conditions of ＜ 80℃,chlorosulfonic acid/glucoside mole ratio ＜ 5, and reaction time ＜ 2 h. Beyond the above reaction conditions, excessive loss of -OH group occurs during hydrolysis. The NMR results indicated a complete sulfation on C-6 and a partial sulfation on the C-2 and C-4 of glucoside.     

硅胶键合的N-丙基三亚乙基四胺氨基磺酸作为可回收固体酸催化剂催化合成2-氨基-4,6-二芳基烟腈(英文)

A simple and efficient procedure for the preparation of silica-bound N-propyl triethylenetetramine sulfamic acid(SBPTETSA) by the reaction of silica-bound N-propyl triethylenetetramine(SBPTET) with chlorosulfonic acid in chloroform is described.Silica-bound N-propyl triethylenetetramine sulfamic acid was employed as a recyclable catalyst for the synthesis of 2-amino-4,6-diarylnicotinonitriles from the multi-component reaction of an acetophenone derivative,an aromatic aldehyde,malononitrile,and ammonium acetate under solvent-free conditions at 100 °C.The heterogeneous catalyst was recycled for five consecutive runs in the optimized multi-component reaction of 4-chloroacetophenone,4-chloroenzaldehyde,malononitrile,and ammonium acetate without significant loses to its catalytic activity.     

Synthesis and characterization of fluorinated poly(aryl ether ketone)s containing 1,4-naphthalene moieties

The new monomer 2,2-bis[4-(4-{4-fluorobenzoyl}-1-naphthoxy)phenyl]hexafluoropropane ( 2 ) was synthesized in a two-step reaction sequence. 2,2-his[4-(1-naphthoxy)phenyl]-hexafluoropropane ( 1 ) was prepared using the Ullmann ether synthesis reaction of 4,4-(hex-afluoroisopropylidiene)diphenol with 1-bromonaphthalene. Friedel-Crafts acylation of 1 with 4-fluorobenzoyl chloride in methylene chloride containing dimethylsulfone selectively afforded 2 in 82% yield. The polycondensation of 2 with various bisphenols in DMAc in the presence of an excess of potassium carbonate as a condensation reagent was carried out at 165°C to quantitatively afford the corresponding fluorinated poly(aryl ether ketone)s containing 1,4-naphthalene moieties. Thermal analysis of the polymers showed them to have T_gs ranging from 194 to 230°C and to be thermally stable in air up with initial weight losses at about 500°C. In addition, these novel polymers exhibited excellent solubility in organic solvents including NMP, DMAc, and chloroform. © 1997 John Wiley & Sons, Inc.     

主链含酰亚胺结构的聚醚醚酮的合成及其性能

以1,4-二苯氧基苯为单体分别与N,N′-(4,4′-二苯甲烷)-双-(3,4-二甲酰亚胺基苯甲酰氯)和N,N′-(4,4′-二苯砜)-双-(3,4-二甲酰亚胺基苯甲酰氯),采用低温溶液缩聚合成了2种主链含酰亚胺结构的聚醚醚酮树脂,聚合物的比浓对数粘度分别为0.98和0.61 dL/g。 用FT-IR、¹H NMR和WAXD进行了结构表征,用DSC和TGA测试了热性能。 结果表明,聚合物有较高的玻璃化转变温度(T_g分别为236和263 ℃),N₂气气氛中热分解温度(5%T_d)分别为529和512 ℃,能溶于N,N-二甲基乙酰胺、N-甲基-2-吡咯烷酮、氯仿和间甲酚等常见的有机溶剂中。     

末端化聚酰胺和交联剂及光酸产生剂所组成的三元负型光敏支化聚酰胺

研究了由未端化支化聚酰胺、交联剂(MBHP)和光酸产生剂(PTMA)所组成的三元负型光敏聚合物体系.其中,不对称ABB′型单体4-(2,4-二氨基苯氧基)苯甲酸3在亚磷酸三苯酯(TPP)和吡啶(Py)的存在下,通过缩合聚合得到支化聚酰胺a,由其1H-NMR数据计算得支化度(DB)为0.36.接着用肉桂酰氯对支化聚酰胺进行末端化.采用IR,1H-NMR,GPC,TG/DTA对支化聚酰胺和末端化支化聚酰胺b的结构和性能进行了表征.由85wt%末端化支化聚酰胺b、10wt%交联剂(MBHP)和5wt%光酸产生剂(PTMA)所组成的光敏聚合物体系,在100℃预烘10min,采用436nm(g-line)紫外光曝光,随后在25℃于二甲基甲酰胺中显影10s,用水漂洗,110℃后烘3min后,得到负型图案,边界清晰且分辨率达40μm.     

含二氮杂萘酮结构聚芳醚腈酮酮的合成及表征

以5种含杂萘联苯结构的单体与2,6-二氯苯腈、1,4-二(4-氟代苯甲酰基)苯为原料进行亲核缩聚反应,制备了一系列含有杂萘联苯结构的新型聚芳醚腈酮酮树脂.其特性粘度在0.51~1.15 dL.g-1之间.采用FT-IR,示差扫描量热仪(DSC),热重分析仪(TGA)对聚合物的结构和性能进行了表征,结果表明,聚芳醚腈酮酮的玻璃化转变温度(Tg)在252~294℃之间,10%热失重温度(Td)在457℃以上,具有优异的耐热性能.聚芳醚腈酮酮均可溶解于N-甲基吡咯烷酮(NMP)、N,N-二甲基乙酰胺(DMAc)、和氯仿等极性非质子型有机溶剂中,聚合物均可溶解于NMP后浇铸得到透明的、韧性好的薄膜.     

1,4-二氢吡啶衍生物合成方法的改进和芳构化研究

改进了Hantzsch合成法,通过一锅煮合成1,4-二氢吡啶衍生物,大大缩短了反应时间,操作简便,发现氯化铁是一个较好的1,4-二氢吡啶衍生物芳构化的氧化剂。     

Rigid-Rod benzobisthiazole polymers with reactive fluorene moieties: Synthesis and characterization

High purity 2,7-fluorenedicarboxylic acid chloride was synthesized in a multistep reaction scheme from 2,7-dibromofluorene. Subsequent polycondensation in polyphosphoric acid of 2,5-diamino-1,4-benzenedithiol dihydrochloride with terephthaloyl chloride and 2,7-fluorenedicarboxylic acid chloride led to rigid-rod benzobisthiazole polymers with reactive fluorene moieties. The proportion of fluorene in the resultant polymers was controlled through reaction stoichiometry. Soluble polymers with intrinsic viscosities as high as 33.7 dL/g (methanesulfonic acid, 30°C) were obtained if the polymerization temperature was not allowed to exceed 165°C. Insoluble, presumably crosslinked polymers were obtained at higher temperature (190–200°C). Thermal characterization of the polymers by differential thermal analysis and thermal gravimetric analysis/mass spectroscopy did not disclose any thermal transition to 450°C. Onset of weight loss in air did not occur until over 550°C.     

含芳酯侧基聚芳醚酮的合成与性能

以偏苯三甲酸酐酰氯(TMAc),对苯二甲酰氯(TPC),1,4-二(4-苯氧基苯甲酰基)苯(p-EKKE)为单体,采用亲电溶液共缩聚,通过改变TMAc、TPC的摩尔比,制备了系列含羧基侧基的聚芳醚酮树脂(PEK-A).在对甲苯磺酸催化下与苯酚进行酯化反应合成了系列主链带芳酯侧基的聚芳醚酮树脂(PEK-COO-Ar).用...     

聚亚胺酮的合成与性能研究

聚酰胺(PA)、聚醚酮(PEK)和聚酰亚胺(PI)等作为高性能材料已被开发并得到应用.这些高性能材料可用于航空、航天、微电子等高新技术领域[1~5].与此同时,为了满足人们对新材料的需求,科学界对新型高性能材料的开发和应用始终没有停止,且备受关注.本文首先通过傅-克酰基化反应合成     

氯化胆碱/草酸型低共熔溶剂氧化脱除模拟油硫化物

通过氯化胆碱和草酸在100℃下搅拌,合成了氯化胆碱/草酸型低共熔溶剂。以氯化胆碱/草酸为催化剂、过氧化氢为氧化剂、咪唑氟硼酸盐离子液体为萃取剂氧化萃取一体法脱除模拟油中的二苯并噻吩(DBT)。考察了反应温度、反应时间、氧化剂加入量、萃取剂类型、硫化物类型等因素对脱硫效率的影响。结果表明,当以咪唑氟硼酸盐为萃取剂,n(H2O2)/n(S)=8、反应温度30℃、反应80 min时,二苯并噻吩的脱除率可以达到95%。催化剂重复使用5次后,脱硫率仍然保持在90%。     

芴基Cardo型聚亚胺酮的分子结构拟、合成及性能

以9,9-双-(3-R-4-氨基苯基)芴(R=H,CH3,F)和1,4-双-(4′-溴苯酰基)苯为单体,通过BuchwaldHartwig交叉偶联反应,缩聚合成了芴基Cardo型聚亚胺酮(PIKF).利用MS软件对其分子结构进行模拟,并通过1H NMR和FTIR等方法进行表征,结果与目标产物吻合.利用凝胶渗透色谱(GP...