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1.
以4,4′-二羰基氯-4″-甲基三苯胺(MeTPADC)、对苯二酰氯(TPC)和硅氧烷化的1,5-二氨基-2,4-二羟基苯二盐酸盐(TBS-DAR)为原料,通过缩合共聚法合成聚酰胺结构预聚体(MeTPA-PrePBO),该预聚物通过高温闭环的方法合成了含甲基三苯胺基团的苯并噁唑共聚物(MeTPA-PBO)。利用核磁共振氢谱(~1 H-NMR)和傅里叶红外光谱(FT-IR)对各预聚体和苯并噁唑共聚物进行了结构表征,利用热重(TG)、紫外-可见吸收光谱(UV-Vis)和荧光光谱等测试方法对改性苯并噁唑共聚物进行了热性能和光物理性能分析。结果表明:预聚体在常规溶剂中具有极好的溶解性,高温热关环处理后的MeTPA-PBO在高沸点溶剂(如二甲基亚砜)中也具有一定的溶解性;在氮气气氛和空气气氛中,高温环境下(500℃以上)均表现出优异的热稳定性;MeTPAPBO具有很窄的能带间隙(2.0eV左右),并可以提供强而稳定的荧光强度。  相似文献   

2.
肖超渤 Augu.  RL 《分子催化》1997,11(5):354-358
报导了聚-γ-N-(β)丁硫基乙基)胺丙基硅氧烷和氯化钯的反应,得到固载在二氧化硅上的聚-γ-N-(β丁硫基乙基)胺丙基硅氧烷钯络合物,并用XPS研究其结构。选用硝基苯,烯丙基环氧丙基醚,烯丙基苯基醚,丙烯腈,烯丙基苯,苯乙烯,环己烯及丁烯等8种底物进行催化加氢,以评价其催化活性。  相似文献   

3.
合成了具有苯侧基的二胺单体1,4-双(4'-氨基苯氧基)-2-(苯基)苯(p-TPEQ), 并与3,3',4,4'-苯酮四羧酸二酐(BTDA)进行缩聚反应, 分别以4-苯乙炔苯酐(PEPA)和4-苯乙炔-1,8-萘二甲酸酐(PENA)作为封端剂, 合成了两个系列的苯乙炔封端的酰亚胺预聚体. DSC测试结果表明, 此类预聚体具有比PETI-5更宽的加工窗口; 利用所合成的预聚体制成了具有较高热分解温度热固性交联PI薄膜. 结果表明, PI预聚体加工性能良好, 其交联后具有优异的力学和热学性能; 同时PEPA封端的预聚体树脂具有比PENA封端的树脂更为优异的综合性能.  相似文献   

4.
以双(2,2,6,6-四甲基-4-哌啶基)癸二酸酯(TMPCA)为软段、1,3-双(1-异氰酸酯-1-甲基乙基)苯(TMXDI)为硬段、甲基丙烯酸异冰片酯(IBOMA)为反应性稀释单体,经甲基丙烯酸羟乙酯(HEMA)封端后得到含有大位阻脲键的聚氨酯丙烯酸酯预聚体;预聚体经紫外光固化,制备得到光敏树脂材料。通过微量热和变温红外对体系中大位阻脲键的热解离机理进行探索,并对光敏树脂的修复性、形状记忆性和二次塑形能力进行了研究。结果表明:大位阻脲键在46~56℃存在吸热效应,预聚体和固化后树脂中均可以观察到异氰酸酯基因(NCO)含量随温度改变发生动态变化,即体系具有动态共价高分子的特点。固化后的光敏树脂修复性能良好,修复后试样的拉伸强度由13.8 MPa恢复至18.4 MPa。此外,含有大位阻脲键的光敏树脂展现出良好的形状记忆和二次塑形能力,并且二次塑形后材料仍能保持80%的弯曲强度。  相似文献   

5.
通过八甲基环四硅氧烷、六苯基环三硅氧烷和1,3 双(γ 氨基丙基)四甲基二硅氧烷在硅醇钾催化下的开环共聚合,合成了α,ω 双(γ 氨基丙基)聚二甲基二苯基硅氧烷预聚体,并用UV、IR、1H NMR、GPC对其化学结构和一些性质进行了表征和测定.  相似文献   

6.
利用脂肪族二元酸酯与乙醇胺反应容易获得的对称二酰胺二醇,经缩聚合成聚酯酰胺预聚体,并针对端羧基和端羟基同时扩链来提高分子量,获得可生物降解的聚酯酰胺.首先将N,N′-二(2-羟乙基)草酰胺(HEOA)或N,N′-二(2-羟乙基)己二酰胺(HEHA)与己二酸和丁二醇缩聚,制备同时带有端羧基及端羟基的脂肪族聚酯酰胺预聚体,通过1,4-双(2-噁唑啉)苯及己二酰双己内酰胺混合扩链剂扩链,获得高分子量脂肪族聚酯酰胺,并通过红外、1H-NMR、DSC及TGA对其结构和热性能进行了表征.结果表明,预聚体在制备过程发生了一定的酯-酰胺交换反应;扩链后聚合物的熔点、熔融焓和热稳定性有所下降;但热稳定性仍接近或略高于聚己二酸丁二酯.  相似文献   

7.
报导了聚-γ-N-(β-丁硫基乙基)胺丙基硅氧烷和氯化钯的反应,得到固载在二氧化硅上的聚-γ-N-(β-丁硫基乙基)胺丙基硅氧烷钯络合物,并用XPS研究其结构.选用硝基苯、烯丙基环氧丙基醚、烯丙基苯基醚、丙烯腈、烯丙基苯、苯乙烯、环己烯及丁烯等8种底物进行催化加氢,以评价其催化活性.结果表明,该催化剂催化效果良好,并且有很好的稳定性.  相似文献   

8.
合成了含有苯乙炔基的二胺单体 3,5-二氨基-4'-苯乙炔苯甲酮(DPEB), 并与3,3',4,4'-联苯四酸二酐(s-BPDA)和1,4-双(4'-氨基苯氧基)-2-(苯基)苯(p-TPEQ)进行了缩聚反应, 以4-苯乙炔苯酐作为封端剂, 合成了交联侧基苯乙炔封端酰亚胺预聚体(n=4). DSC测试结果表明, 引入交联侧基后预聚体依然保持着较宽的加工窗口. 利用所合成的预聚体在370℃热压1 h制备了热固性薄膜. DMA测试结果表明, 引入交联侧基的预聚体树脂具有更高的玻璃化转变温度, 并且其储存模量在玻璃化转变后有很好的保持.  相似文献   

9.
一类含硅亚苯结构的新有机硅预聚体   总被引:6,自引:0,他引:6  
一类含硅亚苯结构的新有机硅预聚体车波王安锋周彩华傅辛福林思聪(南京大学高分子科学与工程系生物材料分子工程和控制释放分子工程室南京210093)关键词有机硅预聚体,对 硅亚苯硅氧烷,热稳定性,合成与表征,开环共聚从分子工程的角度看,以聚有机...  相似文献   

10.
高分子负载膦铂配合物是一类很好的烯烃硅氢加成催化剂,但迄今未见有关螯合型双膦铂配位负载催化剂的报道。1983年,Micholska报道了胺膦双齿配体铑配合物的合成与催化性能。最近,我们合成了气相法二氧化硅负载的聚-4-氧杂-6,7-双二苯膦庚基硅氧烷  相似文献   

11.
A series of cross-linked polyimides (PIs) were prepared via two-step solution polycondensation from 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (BPADA) and 2,5-furandicarboxylic acid-based diamines, N,N′-bis(4-amino-2-(trifluoromethyl)phenyl)furan-2,5-dicarboxamide (TFFDA) and N,N′-bis(4-aminophenyl)furan-2,5-dicarboxamide (p-FDDA), followed by thermal crosslinking reaction with bismaleimide. The thermal crosslinking reaction and its mechanism were studied by FTIR spectra and model reaction analysis, which showed Diels–Alder reaction between furan group and maleimide group played a main role in the thermal treatment. The properties of cross-linked PIs were characterized using dynamic mechanical thermal analysis, thermogravimetric analyses, tensile testing, ultraviolet-visible spectra, and wide-angle X-ray diffraction. The cross-linked polyimide film showed improved solvent-resistance, thermal and mechanical properties with Tg values of 234–306oC, tensile strengths of 82–98 MPa and moduli of 2.3–3.0 GPa.  相似文献   

12.
吴军宁  罗新荣  张辰  万平玉 《合成化学》2012,20(2):143-146,152
在强碱条件下,单体2-(4-辛氧基苯基)-5-[4-(2,5-二溴甲基苯氧基)苯基]-1,3,4-噁二唑和二甲基二对溴甲基苯氧基硅烷发生Gilch脱卤聚合反应,成功合成了一种新型的侧链接有噁二唑的硅氧烷嵌段聚对苯乙烯撑衍生物(8),其结构经FT-IR表征。用UV-Vis,FL和DSC研究了8的光学性能和热稳定性。结果表明,8的热稳定性较单体有所改善;最大发射峰在480 nm。  相似文献   

13.
Benzoxazine monomers namely 1,1-bis (3-methyl-4-hydroxyphenyl)cyclohexane benzoxazine (CBDDM) and bis(4-maleimidophenyl) triphenylphosphine oxide benzoxazine (BMPBBAPPPO) were synthesized and blended with bismaleimide (BMPM) to improve thermal properties of polybenzoxazine. The benzoxazine- bismaleimide (Bz-BMI) hybrid polymer matrices were prepared via in-situ polymerization and their thermal and morphological properties were studied. The chemical reaction of benzoxazines with the bismaleimide was carried out thermally and the resulting product was analyzed by FT-IR spectra. The glass transition temperature, curing behavior, thermal stability, char yield and flame resistance of the hybrid polymer matrices were analyzed using DSC and TGA. The homogeneous structure of the hybrid polymer matrices was determined by SEM and visual observations. Data obtained from thermal studies infer that these hybrid materials possess high thermal stability which can be used as adhesives, sealants, coating and matrices for high performance automobile and microelectronic applications.  相似文献   

14.
Nucleophilic aromatic substitution reaction of 4-aminophenol and also 5-amino-1-naphthol with 2,6-dichloropyridine in N-methyl-2-pyrrolidone (NMP) as solvent, in the presence of potassium carbonate, afforded two aromatic ether diamines. Eight soluble, thermally stable polyamides were prepared by polycondensation reaction of the obtained diamines with aromatic and aliphatic diacid chlorides including terephthaloyl chloride (TPC), isophthaloyl chloride (IPC), adipoyl chloride (AC), and sebacoyl chloride (SC). The prepared monomers and polymers were characterized by conventional spectroscopic methods. Physical and thermal properties of the polymers, such as thermal behavior, thermal stability, solution viscosity, and solubility behavior were also studied.  相似文献   

15.
A diamine was synthesized by two successive reactions.Nucleophilic reaction of 4-hydroxybenzoic acid with terephthaloyl chloride yielded terephthaloyl bis(4-oxybenzoic) acid.Then reaction of this compound with 1,8-diamino-3,6- dioxaoctane via Yamazaki method resulted in preparation of diamine named terephthalic acid bis(4-{2-[2-(2-amino ethoxy)ethoxy]ethyl carbamoyl}phenyl) ester.After fully characterization it was used to prepare new polyimides through polycondensation with different dianhydrides using trimethylchlorosilane.Characterization of polymers was achieved by common methods and their physical properties including inherent viscosity,thermal behavior,thermal stability,crystallinity and solubility were studied.Prepared polyimides showed improved solubility and good thermal stability.  相似文献   

16.
When reaction mixtures of rare earth(III) sulphates and tetramethylammonium sulphate in molar ratios of from 1∶4 to 1∶12 were evaporated at ambient temperature and the concentrated reaction mixture was treated with ethanol, double sulphates with general empirical formula (CH3)4NLn(SO4)2·2H2O (Ln=Ho?Lu and Y) were obtained as reaction products. The crystalline products were identified by quantitative analysis, X-ray powder diffraction patterns and TG, DTG and DTA analysis. They were found to be isostructural. Their thermal decomposition took place in three stages. The temperature range of the dehydration mainly decreased from Ho to Lu. The thermal decomposition in the second and third stages occurred with many thermal events. As final product, Ln2O(SO4)2 was obtained.  相似文献   

17.
过氧铌杂多钨酸盐热分解动力学参数的测定   总被引:9,自引:0,他引:9  
钼和钨的杂多配合物由于其高催化活性及抗病毒性吸引着人们的关注[1]。杂多配合物的组成改变能调变其酸性、氧化性、反应性等,因此,混配型杂多配合物的研究近二十年来十分活跃。铌取代的杂多配合物在催化方面具有很独特的性质,其催化的工业应用及其机理已引起广泛的兴趣[2]。我们发现,过氧铌杂多配合物比非过氧杂多配合物具有更高的催化活性[3]。杂多酸盐的热稳定性是影响多相催化活性的重要性质,迄今有关过氧杂多配合物的热性质和热分解反应动力学参数的研究未见报道。本文用TG、DTA、DSC溶解度试验,变温红外和X一…  相似文献   

18.
首次以H4SiW12O40 * 22H2O和(NH4)2C2O4 * H2O为原料,室温固相反应合成出(NH4)4SiW12O40纳米微粒;用元素分析、 FTIR确定产物的组成和结构; XRD、 TEM和BET对产物的形貌、晶粒尺寸和比表面积进行了表征; TG-DTA确定了产物的稳定温区.结果表明,产物为纳米粒子,平均粒径为60 nm,比表面积为108.7 m2/g,在430℃以下具有良好的热稳定性.在固相反应中,研磨和放热反应热效应能加快反应物扩散速率和生成物成核速率,使产物粒径减小;反应物含有结晶水和生成物H2C2O4 * 2H2O,对形成小粒径的(NH4)4SiW12O40纳米粒子起关键作用.  相似文献   

19.
Biscitraconimides incorporated with 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BTDA) and pyromellitic dianhydride (PMDA) were synthesised. Their curing behavior as well as thermal stabilities were investigated. The intermediate amic acids were prepared by the reaction of 4-amino 4′-citraconamic acid diphenyl sulphone, 4-amino 4′-citraconamic acid diphenyl ether, and 12-amino 1-citraconamic acid dodecane with BTDA and PMDA, respectively. Six amic acids formed were then imidized by cyclocondensation with acetic anhydride. The imide monomers were obtained and these were cured at 225–240°C. The thermal stabilities of the polymers so formed were investigated and compared. © 1996 John Wiley & Sons, Inc.  相似文献   

20.
A new cyanate ester monomer, 1,1-bis(3-methyl-4-cyanatophenyl)cyclohexane has been synthesized and characterized. Epoxy modified with 4, 8 and 12% (by weight) of cyanate ester were made using epoxy resin and 1,1-bis(3-methyl-4-cyanatophenyl)cyclohexane and cured by using diaminodiphenylmethane. The cyanate ester modified epoxy matrix systems were further modified with 4, 8 and 12% (by weight) of bismaleimide (N,N′-bismaleimido-4,4′-diphenylmethane). The formation of oxazolidinone and isocyanurate during cure reaction of epoxy and cyanate ester blend was confirmed by IR spectral studies. Bismaleimide-cyanate ester-epoxy matrices were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and heat deflection temperature (HDT) analysis. Thermal studies indicate that the introduction of cyanate ester into epoxy resin improves the thermal degradation studies at the expense of glass transition temperature. Whereas the incorporation of bismaleimide into epoxy resin enhances the thermal properties according to its percentage content. However, the introduction of both cyanate ester and bismaleimide influences the thermal properties according to their percentage content. DSC thermogram of cyanate ester modified epoxy and bismaleimide modified epoxy show unimodel reaction exotherms. The thermal degradation temperature and heat distortion temperature of the cured bismaleimide modified epoxy and cyanate ester-epoxy systems increased with increasing bismaleimide content. The morphology of the bismaleimide modified epoxy and cyanate ester-epoxy systems were also studied by scanning electron microscopy. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

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