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1.
Abstract

A multistep kinetic process is postulated to describe the pyrolysis of nylon 6–6, phenolic CTL-91LD (a phenolic novalac resin), and their composites. Kinetic coefficients are derived from thermogravimetric analysis data (TGA) at heating rates varying from 3–60°C/min for each component. Three correlation techniques are used to obtain consistent coefficients. A two-step kinetic equation is derived to describe the phenolic pyrolysis and a single-step kinetic equation is found to adequately represent nylon 6–6 pyrolysis. These equations are then combined to obtain an overall pyrolysis rate equation for the composite.  相似文献   

2.
尼龙6,6(PA_(6,6)及其共混物结晶性能的研究   总被引:3,自引:0,他引:3  
<正> 尼龙6,6(PA_(6,6))是一种典型的结晶性工程塑料,被广泛应用于纺织、机械制造等行业,但其加工温度范围较窄,耐热性差。聚醚砜(PES)具有较高的玻璃化转变温度,是非晶聚合物,可以诱发某些结晶聚合物结晶。PES与PA_(6,6)共混体系的研究报道较少,本文用熔融法将PES与PA_(6,6)制成共混物,企图改善PA_(6,6)的结晶性,以提高其耐热性,取得了较理想的结果。  相似文献   

3.
热处理对Nylon—11结构的影响   总被引:2,自引:0,他引:2  
刘思杨  马宇 《应用化学》1998,15(4):33-36
对不同温度热处理过的Nylon-11样品,采用广角X射线衍射(WAXD),根据X射线衍射强度理论,用多重峰图解分峰方法研究了Nylon-11结构的变化,并导出了计算Nylon-11结晶度的公式.所得结果与密度法、DSC法进行了比较.同时也给出了Nylon-11的有关热力学参数,  相似文献   

4.
Using microporous affinity membrane in separation has advantages of large specific area,low backpressure and fast separation ratel. This led to obtain high purity proteins invery short time and reduce the possibility of denaturation of biomelecules in largelysimplified separation process. Nylon membrane offers narrow pore size distributionand good mechanical rigidity. However, nylon membrane has low concentration ofprimary amino group and nonspecific adsorption of protein'. To solve these prob…  相似文献   

5.
Jian-Mei Lu  Hui Ma  Sha-Sha Li  Dan Ma  Li-Xiong Shao 《Tetrahedron》2010,66(27-28):5185-5189
2,2′-Diamino-6,6′-dimethylbiphenyl was found to be an efficient ligand in the palladium-catalyzed Suzuki–Miyaura coupling reactions of aryl iodides, bromides, and chlorides and Mizoroki–Heck reactions of aryl iodides and bromides. Under appropriate conditions, all reactions gave the desired products in moderate to excellent yields. The ligand is inexpensive, air-stable and easy to available.  相似文献   

6.
Nylon I I is a high-performance semicrystalline polymer which was used widely in manyfields. In recent years, the curious ferroelectric and piezoelectric propel'ties of nylon I Iwere foundl'2. It is well known that piezoelectricity is related to the crystal form ofNylon I 1.The sample was mounteds in a capillary (diameter was Zmm) within a small ovenwith mica windows. The scattered intensity was recorded from Q = 0.2 to 6.5 A-] (Q =ursine/~) using steps of AQ=o.o5A-'. The values of the p…  相似文献   

7.
Zusammenfassung Es wurde der Einflu? einer Trockenhitzebehandlung auf Nylon 6-Fasern untersucht, deren Aminogruppen vor der Erhitzung chemisch umgesetzt wurden. Hierbei konnte gezeigt werden, da? durch derartige Reaktionen eine Verbesserung der Hitzebest?ndigkeit von Nylon 6-Fasern erreicht wird.  相似文献   

8.
9.
电驱动条件下膜分离性能的研究对膜在微流控芯片等微小器件中的应用具有重要的指导意义.研究了界面聚合的尼龙6,6膜的电驱动分离性能,并考察了电场强度、通电时间和温度等操作条件对SO42-和Cl-离子透过性能的影响.结果表明尼龙6,6膜具有较好的SO24-和Cl-离子透过性能,并且透过性能差异不大,离子透过百分比随电场强度和通电时间的增加而增加,而随温度的增加基本保持不变.而对FITC标记的甘氨酸和赖氨酸则能完全截留,截留分子量在500左右,具有部分纳滤膜性质.该膜可望应用于微型器件中氨基酸等有机与生物大分子的电驱动分离和浓缩.  相似文献   

10.
11.
Chitosan-coated nylon membranes which possess a large number of reactive groups of-CH2OH and -NH2 were prepared by coupling chitosan onto the nylon membrane. Then polylysine as ligand was also immobilized onto the composite membranes by 1, 1'-carbonyl-diimidazole activation to prepare affinity membranes for bilirubin adsorption. The results showed that these membranes exhibited high binding affinity capacities for bilirubin and the adsorption isotherm fitted the Freundlich model well.  相似文献   

12.
固定化脂肪酶催化合成6,6'-海藻糖月桂酸酯   总被引:6,自引:0,他引:6  
 以吸附在硅藻土上的假丝酵母(Candidasp.1619)脂肪酶为催\r\n化剂,在无溶剂体系中,研究了月桂酸与海藻糖的酯化反应.结果表明\r\n,反应温度为47℃,pH为7.0,月桂酸与海藻糖的摩尔比大于6时酯化\r\n反应的转化率较高.在3.2mmol(0.64g)月桂酸、0.2mmol(0.07\r\n6g,即53μl浓度为1.43g/ml的糖溶液)海藻糖和200mg固定化脂肪酶\r\n(1000U)组成的反应体系中,于47℃振荡反应36h,以海藻糖月桂酸双\r\n酯计算,酯化程度达95%以上.用有机溶剂提取的反应产物经薄层色谱\r\n提纯后进行13CNMR分析,结果表明,产物主要是6,6’-海藻糖月桂酸\r\n酯,其纯度为90%~95%.  相似文献   

13.
14.
以取代的芳基酮为原料, 合成了一系列6,6-取代芳基富烯, 这些富烯都经过了核磁共振、元素分析、质谱和红外光谱的鉴定. 芳基酮上的取代基决定了合成中所用碱的类型. 对于含吸电子取代的酮, 采用乙醇钠作为碱可以达到很高的产率, 而对于含烷基等推电子取代的酮, 用环戊二烯基钠直接反应是一种比较好的合成方法.  相似文献   

15.
离子聚合物在Nylon-1010/PP共混物中的增容作用曲桂杰,刘景江(中国科学院长春应用化学研究所长春130022)关键词聚丙烯,Nylon-1010,离子聚合物,增容选择离子聚合物作为高聚物共混的增容剂,通过离子间的相互作用可达到增容效果[1]。...  相似文献   

16.
A novel solid-phase extraction (SPE) system, based on a new sorbent of Nylon6/Polypyrrole (PA6/PPy) core–shell nanofibres mat and a new packing format of SPE disks, is presented in this paper. A series of related parameters that may affect the efficiency, such as the kind of eluent and its volume, the amount of nanofibres mat, ionic strength, pH of the sample, flow rate of the sample and volume of the sample, have been investigated systematically. Under the optimised conditions, the target analyte in 10 mL water samples can be completely extracted by a 3.0 mg PA6/PPy nanofibres mat and easily eluted by 400 µL acetonitrile. Around 20 µL elution was injected directly to HPLC-UV for determination, without further concentration. Besides, the nanofibres mat could be repeatedly used up to six cycles. Satisfactory linearity was achieved in the range of 0.1–40.0 ng/mL with a correlation coefficient of 0.9999. The limit of detection (LOD) (3 S/N) was 0.03 ng/mL, which could meet the determination requirements of atrazine as per the European Union legislation, US. Safe Drinking Water Act and the State Environmental Protection Administration of China. The simple, effective and economic method was proposed for the determination of atrazine in environmental water at trace level. The recoveries ranged from 94.73 to 114.92%, with relative standard deviations (RSDs) of 2.5–4.2%, and were obtained from tap water and lake water samples with atrazine at 2.0 ng/mL, suggesting the actual feasibility of the proposed method in environmental water samples.  相似文献   

17.
Reaction of 6,6′dideoxy-6,6′di-iodo-1′,2,3,3′,4,4′-hexa-O-benzylsucrose with triethyl phosphite afforded the corresponding 6,6′-diphosphonate. Selective phosphonylation either at the C-6 or 6-6′ position was also possible providing the corresponding sucrose mono-phosphonates. Reaction of 6,6′-dichloro-hexa-O-benzylsucrose with diphenylphoshine anion afforded the 6,6′-diphosphinosucrose.  相似文献   

18.
19.
The synthesis and photophysical properties of several 6,6″ symmetrically substituted 4′-aryl-2,2′:6′,2″-terpyridine derivatives are reported herein. The UV-Vis spectra in acetonitrile as well as in dichloromethane show two intense bands in the UV areas 252–262 nm and 275–290 nm while the fluorescence emission spectra are only slightly influenced by chemical derivatization.  相似文献   

20.
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