基于水热法制备改性聚磷酸钙的工艺调控、表征及性能EI北大核心CSCD

以12-氨基十二烷酸(12-AA)、丙烯酰氯为主要原料,通过Schotton-Baumann酰化反应对聚磷酸钙(CPP)进行改性。探究了水热反应时间和12-AA用量对CPP改性工艺的影响,并利用Fourier红外、X射线衍射、扫描电子显微镜对产物进行了表征,同时研究了CPP的粒度、接触角和热稳定性能。结果表明:随着水热反应时间与12-AA含量的增加,CPP的产率呈增长趋势,酰化反应过程中体系pH值随反应时间的增加呈减小趋势直至平稳(呈弱酸性,pH=6.2)。当反应时间为12 h,CPP与12-AA的摩尔比为1:3时,产率可达56.70%,粒径较小(588.3±119.7 nm);改性前后接触角由2°提高至61.41°;未改性CPP无明显失重(分解温度为592.92℃),热稳定性良好。改性CPP出现明显失重,分解温度在426.68~461.66℃范围内,仍保持良好的热稳定性。     

基于水热法制备改性聚磷酸钙的工艺调控、表征及性能

以12-氨基十二烷酸(12-AA)、丙烯酰氯为主要原料,通过Schotton-Baumann酰化反应对聚磷酸钙(CPP)进行改性。探究了水热反应时间和12-AA用量对CPP改性工艺的影响,并利用Fourier红外、X射线衍射、扫描电子显微镜对产物进行了表征,同时研究了CPP的粒度、接触角和热稳定性能。结果表明:随着水热反应时间与12-AA含量的增加,CPP的产率呈增长趋势,酰化反应过程中体系pH值随反应时间的增加呈减小趋势直至平稳(呈弱酸性,pH=6.2)。当反应时间为12h,CPP与12-AA的摩尔比为1:3时,产率可达56.70%,粒径较小(588.3±119.7nm);改性前后接触角由2°提高至61.41°;未改性CPP无明显失重(分解温度为592.92℃),热稳定性良好。改性CPP出现明显失重,分解温度在426.68～461.66℃范围内,仍保持良好的热稳定性。     

复合薄膜用水性聚氨酯-丙烯酸酯胶粘剂的合成

以聚醚二元醇、甲苯二异氰酸酯(TDI)、二羟甲基丙酸(DMPA)等为原料合成了聚氨酯预聚体,用丙烯酸羟丙酯(HPA)将其部分封端,制得一种水性聚氨酯丙烯酸酯分散体,再加入乙烯基单体进行自由基引发聚合,制备出水性聚氨酯-丙烯酸酯(PUA)复合乳液。用红外光谱仪(FTIR)、差示量热扫描仪(DSC)、热重分析(TG)、马尔文粒度分析等测试手段,对合成产物进行了结构和性能表征。研究了软硬段质量比、亲水基团含量、丙烯酸酯单体的加入对PUA乳液性能的影响。结果表明,m(软段)∶m(硬段)=2∶1,m(PU)∶m(PA)=4∶1,—COOH质量分数为2.8%,以该乳液配制的胶粘剂应用于包装用CPP/CPP薄膜、OPP/VMOPP薄膜的剥离强度分别达31.9N/m和28.1 N/m。     

垃圾渗滤液中腐植酸的提取研究

采用"NF-两级物料膜-RO"的组合工艺处理垃圾渗滤液,得到膜浓缩液,再从膜浓缩液中提取两种腐植酸样品HA(Ⅰ)、HA(Ⅱ),然后对其进行了含量分析、结构分析和吸附性能研究。结果表明,样品HA(Ⅰ)中的总腐植酸含量为73.34%,游离腐植酸含量为71.12%,样品HA(Ⅱ)中黄腐酸的含量高达13.18%。两种样品中均含有较多的羧基、羰基、羟基等含氧官能团和芳烃类物质以及少量的氯化物。在25℃搅拌的条件下,腐植酸对重金属Cu~(2+)有较好的吸附效果,吸附60 min后,Cu~(2+)的去除率已达到68.4%,且在30 min时腐植酸对Cu~(2+)的吸附就已经达到饱和,说明腐植酸对Cu~(2+)的吸附速度较快。     

含异氰脲酸酯基环氧树脂的合成

为了改善环氧树脂的耐热性与韧性 ,以三羟乙基异氰脲酸酯 (THEIC)为原料 ,与环氧氯丙烷 (ECH)合成了氯化聚醚多元醇 (CPP) ,CPP与氢氧化钠反应制备了一种新型的含异氰脲酸酯基和醚键的液体环氧树脂 (EP) ,并通过IR确定了结构。CPP与氢氧化钠的摩尔比为 1∶3.2 5,在 2 50ml乙醇 ( 0 .1molCPP)中 ,室温反应 3h ,产率 87.7% ,环氧值 0 .36 87。     

相对分子质量分布对双峰聚乙烯薄膜树脂等温结晶动力学的影响

研究了2种双峰聚乙烯薄膜树脂（9455F1 W和9455F1 100）的等温结晶动力学行为,并讨论了相对分子质量分布的双峰相对含量对结晶过程的影响。结果表明,2种样品都呈现双峰分布的特征,且其相对分子质量相差不大,但高/低相对分子质量级分含量不同;其中,9455F1 W样品的高相对分子质量级分的相对含量大,9455F1 100样品的低相对分子质量级分的相对含量大;随低相对分子质量级分含量的增加,样品的结晶速率常数增大,半结晶时间减小,结晶速率增大。     

光固化丙烯酸酯改性氯化聚丙烯的制备及性能研究

为得到光固化丙烯酸酯改性氯化聚丙烯(CPP),首先采用溶液聚合方法,用甲基丙烯酸羟乙酯(HEMA)对CPP进行功能化接枝改性,研究了HEMA含量、反应温度、引发剂含量对接枝率的影响,确定合成丙烯酸酯改性CPP最佳工艺条件为m(CPP)∶m(HEMA)=8.5∶1.5,反应温度100℃,引发剂占CPP及HEMA总质量的3%,接枝率达到6.69%。利用甲基丙烯酰氯对在接枝基础上得到的丙烯酸酯改性CPP进行光固化改性,研究了不同接枝率的丙烯酸酯改性CPP光固化改性前后,以及光固化改性产物光固化前后对表面张力和附着力的影响。结果表明:光固化改性前后,涂层表面张力均能达到40.0 m N/m以上,附着力良好;光固化改性产物光固化后表面性能仍然保持良好,附着力得到提高。     

石墨炉原子吸收法测定凉山彝族植物药中的硒

采用Ni(NO3)2-Mg(NO3)2溶液作为混合基体改进剂,微波消解-石墨炉原子吸收光谱法测定了五种彝族植物药中硒的含量。结果表明:五种样品中硒含量在0.095 9μg·g-1和1.411μg·g-1之间。且该方法的标准曲线线性关系良好(R=0.9989),回收率为95.1%~101.3%,RSD值(n=8)为3.73%~7.56%。所建方法简便、快速、准确、可靠,可用于彝药中硒的含量测定。     

氯化聚丙烯与石油树脂等复配溶液粘度的研究

测定了氯化聚丙烯(CPP)-涂料树脂在甲苯溶液中的粘度,发现体系的粘度主要是由CPP含量决定的。但是,因为不同体系(三元和四元体系)的涂料树脂与CPP相互作用情况不同,所以粘度变化与CPP含量的变化规律并不相同。以石油树脂和醇酸树脂为例,对它和CPP间的相互作用进行了讨论。     

离子色谱法测定钙镁片中钙、镁离子的含量

采用离子色谱法进行了钙镁片中Ca~(2+)和Mg~(2+)的含量测定,过程为:先采用盐酸将样品溶解之后,采用阳离子交换色谱柱分离,用阳离子抑制器,分别进行精密度试验,重复性试验,加样回收率试验,系统适用性试验,最后结果检测。实验结果表明Ca~(2+)和Mg~(2+)的质量浓度处于2~18mg·L~(-1)和0.4~9mg·L~(-1)之间时,具有标准的线性关系,其相关系数都接近于1;Ca~(2+)和Mg~(2+)的检出浓度为0.003mg·L~(-1)和0.015mg·L~(-1),其定量浓度为0.004mg·L~(-1)和0.002mg·L~(-1),回收率也均接近100%;实验测的5批样品中Ca~(2+)的含量分别为13.5%、14.8%、15.0%、16.3%、10.6%,Mg~(2+)的含量分别为5.2%、3.8%、4.5%、6.0%、3.9%。     

Study of crystallization and melting behavior of polypropylene‐block‐polyethylenes copolymers fractionated from polypropylene and polyethylene mixtures

A series of ethylene–propylene block copolymer fractions of differing compositions, while still retaining broad molecular weight distributions, were obtained by fractionation of polypropylene (PP) and polyethylene (PE) copolymers prepared by sequential polymerization of ethylene and propylene. The crystallization and melting behavior of the polypropylene‐block‐polyethylene fractions were studied. It was observed that the major component could suppress crystallization of the minor component, leading to a decrease in crystallinity and melting temperature. Non‐isothermal crystallization showed that crystallization of the ethylene block was less influenced by composition and cooling rate than the propylene block. At fast cooling rates, the ethylene block could crystallize prior to the propylene block. Isothermal crystallization kinetics experiments were also conducted. We found that the block copolymers with minor ethylene components had smaller Avrami exponents (n ≈ 1.0), hence indicating a reduced growth dimension of the PE crystals by the pre‐existing PP crystals. On the other hand, the ethylene block exhibited much larger Avrami exponents in those block copolymers with major ethylene contents. Copyright © 2004 Society of Chemical Industry     

Effect of the structure on the morphology and spherulitic growth kinetics of polyolefin in‐reactor alloys

Four polyolefin in‐reactor alloys with different compositions and structures were prepared by sequential polymerization. All the alloys were fractionated into five fractions: a random copolymer of ethylene and propylene (25°C fraction), an ethylene–propylene segmented copolymer (90°C fraction), an ethylene homopolymer (110°C fraction), an ethylene–propylene block copolymer (120°C fraction), and a propylene homopolymer plus a minor ethylene homopolymer of high molecular weight (>120°C fraction). The effect of the structure on the morphology and spherulitic growth kinetics of the polypropylene (PP) component in the alloys was investigated. The polyolefin alloys containing a suitable block copolymer fraction and a larger amount of PP had a more homogeneous morphology, and the crystalline particles were smaller. Quenching the polyolefin alloys led to smaller crystallites and a more homogeneous morphology as well. Isothermal crystallization was carried out above the melting temperature of polyethylene, and the growth of PP spherulites was monitored with polarized optical microscopy with a hot stage. The alloys with higher propylene contents exhibited a faster spherulitic growth rate. The fold surface free energy was derived, and it was found that a large amount of block copolymer fractions and random copolymer fractions could reduce the fold surface free energy. The structure of the alloys also affected the crystallization regime of PP. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 632–638, 2005     

Crystalline structure of propylene–ethylene copolymer fractions

Crystalline structure were studied on both block and random propylene–ethylene copolymer fractions, which were obtained by temperature rising elution fractionation. The peak characteristic of α-polypropylene (PP) was observed for all fractions, except the fraction eluted at room temperature. A characteristic peak of polyethylene crystals [i.e., (200) planes] was observed in some fractions, indicating the existence of long ethylene sequence in these fractions. This is in accordance with the analysis from Fourier transform infrared spectroscopy and ¹³C-NMR. The γ-form crystal of PP was observed in these copolymer fractions at atmospheric pressure. It is suggested that the insertion of comonomer into the isotactic PP chain makes the crystallizable sequences sufficiently short and produces the γ-form crystal. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:381–386, 1998     

The functions of crystallizable ethylene‐propylene copolymers in the formation of multiple phase morphology of high impact polypropylene

The functions of crystallizable ethylene‐propylene copolymers in the formation of multiple phase morphology of high impact polypropylene (hiPP) were studied by solvent extraction fractionation, transmission electron microscopy (TEM), selected area electron diffraction (SAED), nuclear magnetic resonance (¹³C‐NMR), and selected reblending of different fractions of hiPP. The results indicate that hiPP contains, in addition to polypropylene (PP) and amorphous ethylene‐propylene random copolymer (EPR) as well as a small amount of polyethylene (PE), a series of crystallizable ethylene‐propylene copolymers. The crystallizable ethylene‐propylene copolymers can be further divided into ethylene‐propylene segmented copolymer (PE‐s‐PP) with a short sequence length of PE and PP segments, and ethylene‐propylene block copolymer (PE‐b‐PP) with a long sequence length of PE and PP blocks. PE‐s‐PP and PE‐b‐PP participate differently in the formation of multilayered core‐shell structure of the dispersed phase in hiPP. PE‐s‐PP (like PE) constructs inner core, PE‐b‐PP forms outer shell, while intermediate layer is resulted from EPR. The main reason of the different functions of the crystallizable ethylene‐propylene copolymers is due to their different compatibility with the PP matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

The measurement of compositional heterogeneity in a propylene–ethylene block copolymer

¹³C nuclear magnetic resonance (n.m.r.) and Fourier transform infra-red (FTi.r.) spectroscopies, as well as wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (d.s.c.) and temperature rising elution fractionation (TREF), have been combined to measure the composional heterogeneity of a commercial propylene–ethylene block copolymer. It has been shown that the copolymer contains molecular species with a wide variation in composition, and the copolymer products range from amorphous ethylene–propylene rubbers (EPR) to crystallisable propylene–ethylene statistical copolymers, polyethylene and polypropylene homopolymers as well as blocks of various lengths. The so-called block copolymer was composed of about 15% amorphous EPR, 5% random copolymer, 28% block copolymers with long propylene and long ethylene sequences, and 52% homopolypropylene. The crystallisation and melting behaviour of these fractions have been investigated.     

Stepwise polymerization of propylene and ethylene with Cr(acetylacetonate)3/MgCl2–ethylbenzoate/diethylaluminium chloride catalyst system

During propylene polymerization with the Cr(acetylacetonate)₃/MgCl₂–Et₂AlCl–ethylbenzoate catalyst system which shows high isospecificity for propylene polymerization, it was found that the chain transfer and termination reactions can be neglected. Based on this result, some stepwise polymerizations of propylene and ethylene were carried out with the same catalyst system varying polymerization conditions. The resulting copolymers were separated by temperature rising elution fractionation (TREF) and afforded two fractions which were eluted at different temperatures. From the ¹³C NMR, DSC and GPC analyses of each fraction, it was considered that the corresponding block copolymer existed in the fraction eluted at higher temperature. © 2003 Society of Chemical Industry     

Structure and morphology of a commercial high‐impact polypropylene in‐reactor alloy synthesized using a spherical Ziegler–Natta catalyst

A commercial high‐impact polypropylene (hiPP) was fractionated by temperature‐gradient elution fractionation into nine fractions. All fractions were studied using Fourier transform infrared spectroscopy and differential scanning calorimetry. The amount of ethylene in the fractions was also determined. The results demonstrate that the ethylene–propylene statistical copolymer (or ethylene–propylene rubber, EPR) content in this hiPP is rather low and the amounts of ethylene–propylene segmented copolymer and ethylene–propylene block copolymer (that act as adhesive and compatibilizer between elastomeric phase and matrix, respectively) are negligible. Furthermore, the morphology of the resin was studied using scanning electron microscopy observations of microtome‐cut original and etched samples, which reveals that EPR particles are too large and their distribution inside the matrix is not uniform. Copyright © 2010 Society of Chemical Industry     

聚丙烯高档流延膜专用料的开发应用

聚丙烯流延膜是一类十分重要的薄膜品种。主要介绍了2008年茂名石化聚丙烯高档流延膜专用料CP9008的生产开发及应用情况。结果表明在海蒙特环管工艺生产高乙烯、高熔融指数产品是可行的。目前我们开发的CP9008热封温度为120℃-126℃,比以往的国内产品热封温度降低了10℃-20℃,但较进口料还是偏高。     

Influence of copolymerization conditions on the structure and properties of polyethylene/polypropylene/poly(ethylene‐co‐propylene) in‐reactor alloys synthesized in gas‐phase with spherical ziegler‐natta catalyst

A spherical TiCl₄/MgCl₂‐based catalyst was used in the synthesis of polyethylene/polypropylene/poly (ethylene‐co‐propylene) in‐reactor alloys by sequential homopolymerization of ethylene, homopolymerization of propylene, and copolymerization of ethylene and propylene in gas‐phase. Different conditions in the third stage, such as the pressure of ethylene–propylene mixture and the feed ratio of ethylene, were investigated, and their influences on the compositions, structural distribution and properties of the in‐reactor alloys were studied. Increasing the feed ratio of ethylene is favorable for forming random ethylene–propylene copolymer and segmented ethylene–propylene copolymer, however, slightly influences the formation of ethylene‐b‐propylene block copolymer and homopolyethylene. Raising the pressure of ethylene–propylene mixture results in the increment of segmented ethylene–propylene copolymer, ethylene‐b‐propylene block copolymer, and PE fractions, but exerts a slight influence on both the random copolymer and PP fractions. The impact strength of PE/PP/EPR in‐reactor alloys can be markedly improved by increasing the feed ratio of ethylene in the ethylene–propylene mixture or increasing the pressure of ethylene–propylene mixture. However, the flexural modulus decreases as the feed ratio of ethylene in the ethylene–propylene mixture or the pressure of ethylene–propylene mixture increases. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2481–2487, 2006     

乙烯含量对无规共聚聚丙烯晶型及性能影响的研究

通过差示扫描量热分析、X射线衍射分析以及力学性能测试等方法,研究了不同乙烯含量的无规共聚聚丙烯（PPR）体系中,在添加定量β成核剂的条件下,乙烯含量对PPR结晶行为及热学、力学性能的影响。结果表明,PPR的熔点和结晶温度都随其乙烯含量的减少而升高;乙烯含量较少的体系,有利于β晶的形成;体系中β晶含量的提高,会使样品热变形温度提高,且冲击性能显著增强;乙烯含量的提高,增大了PPR β结晶的调控难度;实验室自制β成核剂,可使乙烯含量为0.25 %~5.1 %（质量分数,下同）的PPR中的β晶含量达到80 %以上。