尼龙1010骤冷退火样品的晶体结构

尼龙1010的晶体结构属三斜晶系.作者最近导出了X射线衍射法(WAXD)测定尼龙1010结晶度的公式,进而考查了等温结晶时结晶温度T_C对结晶度X_C、晶粒尺寸L_(100)和氢键面相对衍射强度R的影响.发现X_C和L_(100)均随T_C升高而增大,达196℃后又减小;而R与T_C的关系则相反,呈线性降低.结晶速率快有利于分子链在垂直于氢键面的(100)晶面生长,但R值却降低了.本文利用WAXD考查了尼龙1010不同骤冷退火条件样品的晶体结构.     

膜载体酶标记dip-stick快速检测西维因的痕量残留

利用直接竞争酶联免疫吸附分析技术研发了一种快速、灵敏的膜载体酶标记dip-stick农残西维因检测方法。该方法以带正电尼龙膜(Millipore)为固相载体,将西维因抗体包被于膜上,包被有抗体的膜插入含有西维因和西维因酶标抗原的混合液中竞争反应10 min后直接目视判断分析结果。该方法的整个检测过程只需15 min,对西维因的检出限可达到10μg.L-1,且稳定性较好。通过与高效液相色谱法(HPLC)比较,验证了该检测方法的有效性,可作为品质控制和快速定性检测的一种有效工具。     

尼龙66/蒙脱土复合材料结晶行为的研究

在密炼机中采用熔融共混法制备蒙脱土重量分数为 2 5 %、4 5 %的尼龙 6 6 /蒙脱土复合材料 .通过DSC法对非等温结晶行为及在 2 2 8～ 2 4 0℃范围内的等温结晶行为进行研究 ,并与纯尼龙 6 6进行比较 .从其等温和非等温结晶行为的研究表明 ,蒙脱土起成核剂的作用 ,它的填入使尼龙 6 6结晶速率提高 ,但填料与基体间的相互作用使其链段运动困难 ,结晶活化能提高 ;在研究的填料含量变化范围内 ,结晶行为变化不大 ,并且找到该复合材料在 2 2 8～ 2 34℃范围结晶对温度的不敏感区 ;对非等温结晶过程分析 ,刘结平 莫志深方程是适用的 ,而Ozawa方程则是不适用的 .     

尼龙1010非等温结晶动力学与机理研究

尼龙１０１０非等温结晶动力学与机理研究朱诚身，王经武，李卓美（郑州大学材料工程系郑州４５００５２）（中山大学高分子研究所广州５１０２７５）关键词尼龙１０１０，非等温结晶动力学，结晶机理，动力学结晶能力尼龙１０１０的结晶动力学，无论是等温还是非等温，研...     

γ-射线辐照对尼龙6纤维结构的影响

<正> 过去的大多数研究表明,高能射线辐照会引起聚乙烯及聚丙烯等稀烃类聚合物分子链交联及降解,而且会导致结晶度下降。张利华等人最近的研究表明,对于尼龙1010塑料,仅当辐照剂量高到一定程度后,辐照才会破坏结晶。此外,Stowe等人曾经研究过近紫外线对尼龙66纤维结构的影响,结果表明,在空气气氛中的近紫外辐照主要导致尼龙66纤维降解,并使纤维结晶度提高。有关高能射线辐照对高度取向的合成纤维结构及性能的影响的研究尚不多见。本工作将讨论γ-射线对于尼龙6纤维结构的影响。     

Carboxylic acid functionalization of nylon 6 by radiation grafting and conversion to zinc salts: Effects on physical properties

 Functionalization of polymers by grafting monomeric species on to the backbone of molecular chains with the use of γ-radiation has been used extensively. In this work methacrylic acid was grafted onto a commercial grade of polycaproamide (Nylon 6) by preirradiating the polymer granules to 15 kGy at a rate of 1.0 kGy per hour and subsequently immersing these in a 10% aqueous solution of methacrylic acid in the presence of small quantities of FeSO₄ as homopolymerization inhibitor. The polymer was subsequently neutralized by mixing it with zinc acetylacetonate in a laboratory scale melt mixing device. The acid-grafting polymer modification resulted in an increase in glass transition temperature, while the addition of zinc acetylacetonate gave rise to two transitions: The lower transition corresponds to a miscible mixture of free polyamide and acid-grafted polymer, both plasticized with undecomposed zinc compound, while the upper transition corresponds to the zinc salt of the acid grafted polyamide. Through rheological measurements it was shown that both the acid-grafted polymer and the derived zinc salt have a branched structure, possibly containing also some crosslinked domains. Large improvements in solvent resistance were observed for both type of polymer modifications. Received: 13 December 1996 Accepted: 10 February 1997     

Computer experiments on crystalline nylons: structural analysis of nylons with large aliphatic segments

A theoretical study based on force-field calculations has been performed to investigate the structural preferences of crystalline even nylons n with large and very large aliphatic segments. Atomistic energy calculations and Monte Carlo simulations were carried out considering the conventional and forms of nylons 10, 12, 18, 24, and 32. Results indicated that the form is the most favored for nylons 10, 12, 18, and 24. However, the structure was unstable for nylon 32, a polymer in which the density of hydrogen bonds is almost negligible. In this case, the arrangement is energetically more favored than the one.     

Preparation and characterization of nylon 66/montmorillonite nanocomposites with co-treated montmorillonites

In this paper, a new type of organophilic montmorillonites, co-treated by octadecylammonium and aminoundecanoic acid, were synthesized and applied to prepare nylon 66/montmorillonite nanocomposites via melt compounding in a twin extruder. WAXD and TEM characterization indicate that a disordered structure was derived and the montmorillonite platelets dispersed in nanoscale in the nylon 66 matrix. The nanocomposites with co-treated montmorillonite display comparatively higher strength and modulus compared to nylon 66 matrix.     

DETERMINATION OF DEGREE OF CRYSTALLINITY OF NYLON 1212 BY WIDE-ANGLE X-RAY DIFFRACTION

Based on the X-ray scattering intensity theory and using the approximate expression for the atomic scattering factor, the correction factors for three crystalline peaks and an amorphous peak of Nylon 1212 were calculated and the formula of degree of crystallinity of Nylon 1212 was derived by a graphic multipeak resolution method. The degree of crystallinity calculated from the WAXD method is compatible with those obtained by density and calorimetry methods.     

绝热法研究己内酰胺阴离子聚合尼龙动力学

采用己内酰胺钠盐、N-75缩二脲作为反应催化体系, 确定反应温度在145-160 ℃之间, 通过计算得到动力学参数: 反应级数为准一级、活化能在73.2-77.1 kJ·mol-1之间、指前因子在2.9×1011-3.6×1011 mol1-n·s-1范围内. 本实验条件下测定并计算的反应热为134.5-137.3 J·g-1, 与文献值(138.6 J·g-1)吻合. 并在前人基础上修正并建构了己内酰胺阴离子绝热反应动力学模型, 对反应过程的模拟结果与实验数据基本吻合, 从而证明了本模型的正确合理.