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1.
陈正桂 《浙江化工》2001,32(3):30-30
萜烯树脂是通过萜烯的阳离子催化聚合而制得的低分子碳氢化合物,是一种优良的增粘剂,广泛地应用于热熔涂料、胶粘剂、橡胶、油墨等工业部门。国内基本上都是以优级松节油为原料生产萜烯树脂,迄今还未见有关松油醇副产物制备萜烯树脂的报道。萜烯树脂为淡黄色透明脆性固体、易溶于苯、甲苯、松节油等机溶剂,不溶于水甲醇、乙醇等,软化点大于等于80℃。色泽小于等于10(铁钴法)。1聚合工艺路线2实验操作2.1原料精制红细含宁烯90%溶剂甲苯化学纯催化剂Lewis酸催化体系2.2萜烯树脂的制备在装有搅拌器的500m…  相似文献   

2.
A novel hyperbranched electroactive azo copolymer with different oligoaniline segments that exhibits an interesting molecular structure was synthesized using an oxidative coupling polymerization approach. The detailed characteristics of the obtained copolymer were studied systematically by Fourier-transform infrared (FTIR) spectra, nuclear magnetic resonance (1H NMR), gel permeation chromatography (GPC) ,and X-ray powder diffraction (XRD). The thermal resistance of the copolymer was investigated by thermogravimetric analysis (TGA). Using cyclic voltammetry (CV), we explored the electrochemical behavior of this novel copolymer. Moreover, the photoisomerization and doping processes of the copolymer were monitored with UV?Cvis spectra. The dielectric properties of the copolymer were investigated in detail, and interesting results were obtained: firstly, a large increase in the dielectric constant was achieved by doping the conjugated oligoaniline segments with HCl; secondly, this HCl-doped copolymer possessed much higher dielectric constants than the corresponding linear polymer, mainly due to its branched molecular architecture.  相似文献   

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The growth of the green algaChlorella pyrenoidosa was inhibited by terpene alcohols and the terpene aldehyde citral. The strongest activity was shown by citral. Nerol, geraniol, and citronellol also showed pronounced activity. Strong inhibition was linked to acyclic terpenes containing a primary alcohol or aldehyde function. Inhibition appeared to be taking place through the vapor phase rather than by diffusion through the agar medium from the terpene-treated paper disks used in the system. Inhibition through agar diffusion was shown by certain aged samples of terpene hydrocarbons but not by recently purchased samples.  相似文献   

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采用异戊二烯与金属锂在环己烷和四氢呋喃中直接反应制备了负离子聚合用双官能度有机锂引发剂,它是异戊二烯的齐聚物。该齐聚物相对分子质量分布窄,聚合度可控。引发剂浓度能够在0.2-1.2mol/L调节。四氢呋喃与活性种摩尔比为4-6。  相似文献   

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采用自制异戊二烯齐聚物双官能度有机锂引发剂,2步加料合成了苯乙烯/丁二烯三嵌段共聚物,所合成的SBS具有较窄的相对分子质量分布、较低的l,2-结构和良好的物理机械性能。  相似文献   

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介绍了合成辐射固化星形齐聚物的方法和线路,对各方法和路线特点进行了评定;对由阴离子聚合法合成辐射固化星形齐聚物的封端反应进行了系统评述。  相似文献   

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We report synthesis and characterization of dimer and oligomer acids from chaulmoogra oil. (R)-Methyl hydnocarpate (methyl ester of the major fatty acid component of chaulmoogra oil) was brominated to give threo-2,3-dibromocyclopentane-1-methyl undecanoate. Formation of two diastereoisomers, viz., threo-2(R),3(R)-dibromocyclopentane-1(R)-methyl undecanoate and threo-2(S),3(S)-dibromocyclopentane-(R)-1-methyl undecanoate, was observed. Dehydrobromination of bromo derivatives using alcoholic KOH gave a cyclopentadiene derivative as intermediate, which underwent Diels-Alder reaction to give dimer and oligomer fatty acids. The products were characterized by ultraviolet, direct exposure probe-mass spectroscopy, 1H nuclear magnetic resonance (NMR), and 13C NMR spectroscopic techniques.  相似文献   

9.
液体异戊二烯橡胶的合成及结构表征   总被引:1,自引:0,他引:1  
采用锂系阴离子聚合工艺合成4种液体异戊二烯橡胶(LIR),用红外光谱及核磁共振对合成样品的结构进行了剖析并与国外样品进行了对比,结果表明合成LIR的结构与国外同类样品相当。  相似文献   

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A new method is described to introduce pure blocks of ethylene, isoprene, and styrene into polymer systems composed of these moieties. This method involves the selective catalytic hydrogenation of 1,4-butadieine-1,4-isoprene and 1,4-butadieine-1,4-isoprene-styrene co and terpolymers to form ethylene-1,4-isoprene and ethylene-1,4-isoprene-styrene co and trepolymers. The properties of these polymer systems are discussed as a function of composition and degree of polymerization. A useful feature of this technique is the preparation of ABA type thermoplastic elastomers.  相似文献   

11.
Styrenation of fatty vinyl ether polymers in dipentene at 145–165C gives products containing from 20 to 67% styrene by weight but little or no unreacted monomeric styrene remained. After 27 mounths no gelation occurred in these products. Apparently dipentene serves as an effective chain transfer agent during styrenation, keeps the growing polymer chains short, and reduces crosslinking reactions. The amount and type of unsaturation needed in the fatty side chains of the polymer to produce homogeneous products were studied. Ultraviolet and infrared analyses were useful in determining the function of unsaturation in these reactions. Tests on baked films from these products showed that as the amount of styrene was increased, both hardness and alkali resistance were significantly increased. Films prepared from products containing 34 and 67% styrene had Sward hardness values of 10 and 60, and alkali resistance of 33 days and over 65 days, respectively. Films from products prepared in aromatic solventsversus dipentene at the same styrene level showed no difference in hardness, but the alkali resistance of the “dipentene film” was greater. Presented at the AOCS meeting in St. Louis, Mo., 1961. A laboratory of the No. Utiliz. Res. & Dev. Div. ARS, USDA.  相似文献   

12.
The structural characterization of polyesters of citric acid (CA) with ethylene glycol and long‐chain aliphatic alcohols (ROH), prepared by the composition of the reaction mixture being adjusted slightly away from stoichiometric equivalence, was performed with 1H‐ and 13C‐NMR spectroscopy. The aliphatic alcohols employed were 1‐decanol, 1‐dodecanol, and 1‐octadecanol. The 13C‐NMR carbonyl region presented four groups of signals, two corresponding to the ester groups and two corresponding to the acid groups. However, symmetric and asymmetric groups of CA moieties were identified in the 13C‐NMR spectra. The ester yield from ROH decreased as the number of carbon atoms in the alcohols increased. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 302–306, 2003  相似文献   

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A study was conducted to synthesize oligoester alcohols from dimethyl terephthalate production wastes via transesterification with diethylene glycol and trimethylol propane. The oligoester alcohols obtained are suitable for preparing rigid polyurethane foams. The oligoester alcohols from trimethylol propane possess good physical and mechanical properties. The oxygen indices indicate that the polyurethane foams exhibit improved resistance to combustion due to the increased content of aromatic nuclei in the oligoester alcohols.  相似文献   

16.
周忠强 《化学试剂》2006,28(9):521-522,540
由天然樟脑合成了两个新的手性酰胺醇,并对其在二乙基锌对苯甲醛的不对称加成反应中的催化性能进行了研究。这两个手性酰胺醇表现出中等程度的催化活性但没有表现出不对称诱导作用。  相似文献   

17.
聚烯烃产品中低聚物的分析   总被引:1,自引:0,他引:1  
通过对CX(淤浆均聚 + 淤浆共聚 + 离心脱除低聚物)工艺产品中离心机脱除低聚物前后聚合物的分子量分布的分析对比,得出离心机可以脱除低聚物,最终产品中低聚物含量降低;通过力学和热稳定性的研究,证明了产品经离心机脱除低聚物后力学及热性能均有所提高;利用核磁分析了烯烃淤浆聚合工艺难以生产高共聚单体含量的聚乙烯牌号的原因。  相似文献   

18.
Summary Methods to synthesize dimethylsiloxane oligomers and macromonomers with aromatic diamino function were studied. Telechelic oligomers having 4-aminophenyl groups on both ends of the molecule(1) were synthesized by the reaction of 4-[N,N-bis(trimethylsilyl)amino]phenyllithium with ,-dichlorooligodimethylsiloxane. Reaction of the lithium reagent with methyltrichlorosilane followed by methanolysis and successive hydrolysis gave methylbis(4-aminophenyl)silanol. Reaction of the silanol with oligodimethylsiloxane with mono-dimethylchlorosilyl function at one end of the molecule gave dimethylsiloxane oligomers having methylbis(4-aminophenyl)silyl function at one end of the molecule(2).Protection of the amino groups of bis(4-aminophenyl)methane as bis(trimethylsilyl)amino group, metalation of methylene group by butyllithium-N,N,N,N-tetramethylethylenediamine (TMEDA), followed by the reaction with mono-dimethylchlorosilyl-functionalized oligodimethylsiloxanes gave oligodimethylsiloxanes having bis(4-aminophenyl)methyl function at one end of the molecule(3).Polydimethylsiloxane macromonomers having bis(4-aminophenyl)methyl function were obtained by end-capping the living end of the polymerization of hexamethylcyclotrisiloxane(D3) by lithium bis[4-{bis(trimethylsilyl)amino}phenyl]methide with trimethylchlorosilane and removal of the protecting group.  相似文献   

19.
钛系异戊二烯橡胶的合成及性能表征   总被引:1,自引:0,他引:1  
以异戊二烯(Ip)为单体,Al(i- Bu)3(简称Al)/TiCi4(简称Ti)为催化剂(以100 g lp计,Al、Ti的用量分别为2.27~3.77 mmol、4.08 ~6.81 mmol),芳香醚为活化剂,合成了异戊二烯橡胶(IR),考察合成钛系IR的影响因素,并将合成的钛系IR与日本Zeon公司生产的钛系I...  相似文献   

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