激光裂解色谱法鉴定聚合物

1 前言 本文用CO_2激光裂解器和SC—1001型气相色谱仪组成一套裂解色谱装置,主要对聚乙烯、聚氯乙烯、聚丙烯这三种聚合物进行了裂解色谱试验,得到了各自的裂解色谱图,借以鉴定聚乙烯类、聚氯乙烯类、聚丙烯类的聚合物。2 实验部分     

EA-AA共聚物增容的PVC-木质素共混物的热稳定性

木质素分子中含有阻碍酚结构,可抑制基于自由基连锁机理的反应。而聚氯乙烯(PVC)的热降解属于自由基反应,因此用木质素与PVC共混,共混物的热稳定性应高于PVC,但PVC与木质素直接共混物的热稳定性一般都劣于PVC。制备了丙烯酸乙酯(EA)-丙烯酸(AA)共聚物乳液并用其对木质素粉末进行包覆处理。用处理后的木质素与PVC进行共混制备成PVC-木质素共混物。用热重分析法研究了共混物的热稳定性,并据扫描电子显微镜观测结果,结合木质素分子结构推测了共混物热稳定性的改善机理。结果表明,木质素用EA-AA共聚物处理后,共混物的热稳定性得到了明显改善,且优于PVC参照样(其初始分解温度和最大分解速率温度分别比PVC参照样高13℃和27℃左右)。扫描电子显微分析表明,木质素经丙烯酸酯共聚物处理后,与PVC的相容性改善显著,在PVC基体中分散良好。木质素羟基与EA-AA共聚物羧基的结合和分散颗粒的减小有效减弱了木质素的脱水作用,抑制了它对PVC的自催化脱氯化氢的促进作用,从而有效发挥了它的阻碍酚结构对PVC自催化脱氯化氢过程的抑制作用。     

聚合物共混物的形态结构与物性

本文主要对高分子材料的嵌段、接枝共聚物及聚合物共混物的形态结构与物性进行定性叙述。     

乙烯-辛烯共聚物/SBR共混物的研究

研究了乙烯-辛烯共聚物（POE）/SBR共混物的力学性能和相态结构。结果表明,随着POE8180（辛烯质量分数为0.28）/SBR共混比（除50/50外）增大,共混物的力学性能提高,POE8003（辛烯质量分数为0.18）用量不超过40份时,随着POE8003/SBR共混比增大,共混物的力学性能提高;POE8003制成粘度较大的炭黑母粒后再与SBR母炼胶共混,可提高共混物的力学性能;POE8180与SBR的共混温度为120℃时共混物的综合力学性能最佳;POE8180/SBR共混物为两相结构,POE8180/SBR共混比为40/60时共混物呈互穿网络结构。     

功能性聚合物共混物

本文简介了功能性聚合物共混物（ＦＰＢｓ）的概念和类型，对防静电性、导电性、离子交换性、低收缩应力性、低双折射性、阻隔性共混物（ＰＢｓ）的组成、形态结构、性能及应用进行了详细的论述。     

用ES共聚物对PE—PS共混物增容的研究

准无规乙烯－苯乙烯共聚物是由一种限定几何结构的催化剂制备,对聚乙烯－聚苯乙烯共混物的增容是非常有效的。     

高聚物共混物中的界面效应

本文从理论和实验研究两方面讨论了高聚物共混体的相界面结构,表征相界面的参数,以及控制相界面结构形态的实验方法。     

用裂解气相色谱法对乙-丙共聚物组成的测定

介绍了用裂解气相色谱 ( PGC)法对乙 -丙共聚物 (塑料 )组成的定量测定 ,用不同配比的共混物校准共聚物组成 ,获得满意的结果。是一种较实用、简易的定量方法。     

MVQ/EPDM共混改性用于生产耐热水蒸气橡胶制品的研究

研究了硫化剂、相容剂、炭黑及共混比对 Ｍ Ｖ Ｑ／ Ｅ Ｐ Ｄ Ｍ 共混物力学性能的影响。提出了耐热水蒸气橡胶制品的合理配方, 指出了提高共混胶的相容性及共硫化是获得优异性能产品的关键。     

Gas evolution during pyrolysis of various Colorado oil shales

Rates of evolution of C0₂, CO, H₂, CH₄ and the C₂ and C₃ hydrocarbons during the pyrolysis of seven Colorado oil shales have been measured. These shales, which are from various depths at two different sites, yield 34–255 ¦ of oil per tonne raw shale (9–61 US gal of oil per short ton raw shale) and linear heating at a rate of 2°C min⁻¹ was used for the retorting of all samples. The objective of the study is to monitor variations in gas evolution from shales of different organic content and from various stratigraphic and areal locations. Comparisons between shales from each site are made together with correlations with data from Fischer assays. A kerogen concentrate (mineral fraction removed by HCl-HF treatment) and retorted shale from a Fischer assay are also included. The ability of a kinetic model due to Campbell et al. to predict gas evolution is tested and it is found necessary to modify slightly some of the stoichiometric coefficients to obtain good agreement. The resultant kinetic model should adequately describe the gas and oil evolution behaviour of shale from the upper portion of the Green River formation.     

聚丙烯酸、丙烯酸共聚物的合成与应用

介绍了聚丙烯酸、丙烯酸共聚物的合成方法,以及在工业循环冷却水中的应用、原理、性能。     

硅橡胶／丁苯橡胶并用胶的硫化特性及性能研究

研究了硅橡胶与丁苯橡胶的质量比对硅橡胶／丁苯橡胶并用胶的硫化性能、力学性能及耐热老化性能的影响;探索了共混工艺对硅橡胶／丁苯橡胶并用胶力学性能的影响。结果表明,热捏合共混法能够改善硅橡胶与丁苯橡胶的相容性,提高硅橡胶／丁苯橡胶并用胶的力学性能,热捏合工艺为150℃×1h。硅橡胶与丁苯橡胶的最佳质量比为90：10。此时,与硅橡胶相比,并用胶的拉伸强度为10．58MPa,提高了28．0％;撕裂强度为51．6kN／m,提高了261％。     

Compatibility Studies and Characterisation of a PVC/NR Blend System Using NR/PU Block Copolymer

Summary Polyvinyl chloride (PVC) has been blended with masticated natural rubber (NR₅) in the presence of a compatibiliser. A block copolymer of NR and polyurethane (PU) based on propylene glycol (PG) and toluene diisocyanate (TDI) was used as the compatibiliser. Compatibilising effect of this block copolymer on PVC/NR₅ (90/10) blend system was investigated by solution viscometry and optical microscopy. Testing and analysis of the blends showed that the mechanical and morphological properties are functions of compatibiliser concentration. Incorporation of 10 parts of NR₅ into PVC caused deterioration of tensile properties of the latter, which were recovered on the addition of 1.5 weight per cent of the compatibiliser. Besides, the tensile impact strength of PVC gets improved greatly. This was attributed to the enhanced interfacial adhesion between PVC and NR caused by the compatibiliser. The modification at the interface leads to finer and uniform distribution of NR domains in the PVC matrix.     

反气相色谱研究甲基丙烯酸甲酯-甲基丙烯酸乙酯共混改性氰酸酯的结晶行为

利用甲基丙烯酸甲酯-甲基丙烯酸乙酯共聚物（BT）对氰酸酯（CE）进行共混改性,应用反气相色谱法测定了共混改性前后 CE 的结晶参数,包括结晶度、熔点、熔程,讨论了正构烷烃探针分子碳链长度以及共混比例对测定结果的影响。研究结果表明:改性后聚合物结晶度和熔点有了显著的降低,其中以70% BT 共混改性后的变化最大,结晶度降低了约16.94%,熔点降低了约20K。聚合物结晶度的测定随正构烷烃探针分子碳链长度的增加而降低。     

利用裂解气相色谱分析丙烯酸树脂的组成

采用裂解气相色谱仪迅速获得了溶剂型丙烯酸树脂中溶剂和合成树脂的组成。对于溶剂系统,柱箱从45℃开始,保温5 min,以5℃/min的速率升到200℃,保温5 min,裂解温度和裂解时间分别为200℃和10 s;对于固体树脂,柱箱从40℃开始,保温5 min,以7℃/min的速率升到250℃,保温5 min,裂解温度和裂解时间分别为550℃和30 s。对于含量较高的组分,其相对标准偏差<0.5%。树脂组成的分析结果与验证结果符合良好。该方法简便易行,对于丙烯酸树脂及其涂料生产企业开发新产品和了解市场信息,具有重要的参考价值。     

基于分子动力学模拟的轮胎橡胶气相热解产物反应机理

运用分子动力学的方法,对轮胎橡胶的热解过程进行了模拟,并结合模拟结果和密度泛函数对其气相产物的反应路径进行推测计算。模拟结果表明,热解过程主要分为两个阶段,低温热解阶段发生的主要反应是橡胶长链断裂形成单体,主要产物为异戊二烯、苯乙烯和1,3-丁二烯;高温热解阶段发生的主要反应是单体进一步生成小分子气体,产物中CH₄、H₂、C₂H₄占大部分,还有少量C₂H₆、C₃H₆。其中CH₃·攻击异戊二烯和苯乙烯单体夺取特定位置的H·是生成CH₄的最优路径,H·攻击苯乙烯单体夺取特定位置的H·是生成H₂的最优路径,CH₂CH·攻击1,3-丁二烯单体夺取特定位置的H·是生成CH₂CH₂的最优路径。本文还将热解产物分别跟天然橡胶单独热解和天然橡胶与丁苯橡胶共热解的热解产物做对比,为废旧轮胎橡胶热解得到特定的气相产物和催化热解提供理论依据。     

Determination of Thermodynamic Interactions of the Pvc-Pmma Blend System by Inverse gas Chromatography

In this study, the sorption enthalpy (δH^S1), sorption free energy (δ^G1), sorption entropy (δ^S1), enthalpy, and free energy at infinite dilution (δ^H1 and δ^G1) values were calculated for selected probes such as alcohols, ketones, acetates, cyclic ethers, aromatics, and alkanes in the temperature range 403-433 K for poly(methyl methacrylate) (PMMA), poly(vinyl chloride) (PVC) homopolymers, and the PVC-PMMA blend system. The values of the Flory-Huggins interaction parameters χ1(23) have been calculated in this temperature range and show the importance of specific interactions between the polymers and the solvents. The values of the polymer-polymer interaction parameters χ23(for the temperature range 403–433 K) were found to change from +3.57 to +1.16 for alcohols, from +2.99 to +0.52 for ketones, from + 1.60 to ?0.48 for acetates, from +0.96 to ?1.46 for cyclic ethers, from +2.66 to +0.12 for aromatics, and from +8.73 to +1.06 for alkanes.