SBS和MMA—丙烯酯丁酯接枝聚合物的溶解性和溶度参数的订定

研究了接枝最为２１．９２％的接枝聚合物ＳＢＳ－ｇ－Ｐ（ＭＭＡ－ＢＡ）在４１种溶剂中的溶解性，表明该聚合物能完全溶解在氯仿、四氯化碳、苯、甲苯、乙酸乙酯、二氧化己环等溶剂中。用浊度滴定法测定该接枝聚合物的溶度参数为９．０３（ｃａｌ／ｃｍ＾３）＾１／２，用特性粘数法测定的溶度参数为９．００（ｃａｌ／ｃｍ＾３）＾１／２。     

新型导电高分子材料——聚吡咯/聚(丙烯酸丁酯-苯乙烯-丙烯酸)的研究

将丙烯酸丁酯、苯乙烯和丙烯酸以３０∶１５∶４的质量比运用乳液聚合法合成了新型三元共聚物Ｐ（ＢＳＡ）。当Ｐ（ＢＳＡ）与原硅酸乙酯（ＴＥＯＳ）以９∶１的质量比反应１ｈ后,所得交联Ｐ（ＢＳＡ）的拉伸强度和扯断伸长率分别达６．３ＭＰａ和５８０％。以该新型共聚物为基体,运用低温氧化聚合法合成了半互穿网络结构的新型导电复合物聚吡咯／Ｐ（ＢＳＡ）。研究了ＦｅＣｌ３用量、吸附反应时间和溶剂性质对复合物导电性能的影响。若ｍ（ＦｅＣｌ３）／ｍ（Ｐ（ＢＳＡ））＝８／９,吸附反应２４ｈ后,复合物的电导率高达２２０Ｓ·ｍ－１。     

自交联型SBS接枝共聚物的合成与粘接性能研究*

研究了在混合溶剂中了二烯－苯乙烯嵌段共聚物（ＳＢＳ）与丙烯酸丁酯（ＢＡ）、甲基丙烯酸甲酯（ＭＭＡ）及交联单体Ｎ－羟甲基丙烯酸胺（Ｎ－ＭＡＡ）进行四元接枝共聚的反应条件及其产物的粘接性能。讨论了引发剂浓度、交联单体用量、单体配比、反应时间及反应温度对接枝共聚物的影响。实验确定的最佳反应条件为：引发剂ＢＰＯ用量为ＳＢＳ用量的１．８％—２．２％；交联单体Ｎ－ＭＡＡ用量为ＳＢＳ用量的１６％—１．８％；ＢＡ／（ＢＡ＋ＭＭＡ）用量比为３５％；反应时间为３５—４．５ｈ；反应温度为８０—８５℃。用红外光谱对接枝共聚物进行了分析鉴定。性能测试显示出该四元接枝共聚物对聚氯乙烯、ＳＢＳ等难粘材料有较高的剥离强度。     

新型高效催化剂气相聚合制备聚乙烯

综合报道了新型乙烯气相聚合ＭＧ型催化剂的制备及其聚合反应性能。研究了采用浸渍反应法制备含ＴｉＣｌ４／ＭｇＣｌ２／ＺｎＣｌ２／ＳｉＯ２醇／Ａｌ（ｉ－Ｂｕ）３的ＭＧ－４型高效催化剂。在压力１．０ＭＰａ下,乙烯聚合催化效率高达４４５￣８８４ｋｇＰＥ／ｇＴｉ,制得了表观密度≥ｇ／０．３７／ｃｍ＾３、重均颗粒分布（２０￣２００目）≥９７．７％、颗粒状态良好的聚乙烯。用ＤＳＣ、ＳＥＭ、ＷＡＸＤ对聚合产物进行了     

新试剂7-(2,4-二羟基苯偶氮)-8-羟基喹啉-5-磺酸与痕量镉的显色反应研究

在微酸性条件下（ｐＨ３．９～４．９），镉与７－（２，４－二羟基苯偶氮）－８－羟基喹啉－５－磺酸（ＤＨＢＡＱＳ）的配合物表观摩尔吸光系数达１．４５×１０５Ｌｍｏｌ－１ｃｍ－１。Ｃｄ２＋浓度范围在０～２０μｇ／２５ｍＬ符合比耳定律。结合ＤＡＭ－ＣＨＣｌ３萃取Ｃｄ２＋与其他干扰离子有效分离，据此测定微量镉效果满意。     

SBS常压加氢反应的红外光谱表征

ＳＢＳ在常压（０．１ＭＰａ）下镍系催化剂Ｎｉ（ｎａｐｈ）２－Ａｌ（ｉ－ｕ）３的加氢反应发生在聚丁二烯链段上,苯乙烯链节不与加氢反应。以芳环Ｃ＝Ｃ在１４９２ｃｍ＾－１处的特征吸收峰为内标导出了采用９１０,９６６,１４１７ｃｍ＾－１进行聚丁二烯嵌段中１,２－链节、顺－１,４链节和反－１,４链节加氢度的定量计算式,     

KTa0.55Nb0.45O3薄膜的介电和铁电及热释电性能研究

在ＢＴ／Ｐｔ／Ｔｉ／ＳｉＯ２／Ｓｉ衬底上用溶胶－凝胶法制备了ＫＴａ０．５５Ｎｂ０．４５Ｏ３（ＫＴＮ）薄膜,０．５μｍＫＴＮ－０．０８μｍＢＴ薄膜在２５℃,１．０ｋＨｚ时,其εｒ＝１１１４,ｔａｎδ＝２．５％;１２℃时,其中Ｐｒ＝２．１μＣ／ｃｍ＾２,Ｐｓ＝４．２μｃ／ｃｍ＾２,Ｅｃ＝５．８ｋＶ／ｃｍ,０．５μｍ厚ＫＴＮ膜的Ｃｕｒｉｅ温度为３５℃;１．０ＫＨｚ时,ＫＴＮ膜的εｒ＝１４１２,估算ＫＴＮ     

正丁醇钛—乙酸钡水解法合成BaTiO3粉体的研究

本文着重研究了Ｔｉ（Ｏ＾ｎＢａ）４－Ｂａ（ＤＡｃ）２水解法合成高纯超细ＢａＴｉＯ３粉体的制备工艺。借助ＴＧＤＴＡ，ＸＲＤ，ＴＥＭ，ＳＥＭ，ＳＡＸＳ和ＩＣＰ－ＡＥＳ等分析手段，研究了ＰＨ值，Ｂａ／Ｔｉ比和（Ｂａ／Ｔｉ）比，反应温度，浸泡处理等对ＢａＴｉＯ２粉体性能的影响，采用本工艺方法合成的ＢａＴｉＯ３粉体，纯度达９９．８０ｗｔ％，比表面积为６８ｍ＾２／ｇ，一次粒子平均粒径４６．７ｎｍ，二次粒子粒径     

聚醋酸乙烯和聚乙烯醇接枝共聚物的制备

在２－甲基丙烯酰氯存在的情况下，用２－巯基乙醇作链转移剂，使醋酸乙烯进行游离基聚合制备一尾端有羟基团的聚醋酸乙烯大分子单体，用凝胶渗透色谱法（ｇ．ｐ．ｃ．）和＾１Ｈ核磁共振（＾１Ｈｎ．ｍ．ｒ．）分光镜测定聚合度、聚合度分布指数和ＰＶＡｃ大分子的官能度。用甲基丙烯酸甲酯（ＭＭＡ）和苯乙烯（Ｓｔ）与ＰＶＡｃ大分子单体进行共聚，并设想在无其它副反应情况下正常地进行聚合。用ｇ．ｐ．ｃ测定其共聚情况。用＾１     

聚乙烯醇存在下耐尔蓝－铈钼、钪钼杂多酸体系连续光度测定铈和钪

在聚乙烯醇（ＰＶＡ）存在下，耐尔蓝（ＮＢ）与铈钼、钪钼杂多酸络阴离子形成离子缔合物，其最大吸收均位于５８５ｎｍ，表观摩尔吸光度分别为εｃｗ＝３．５２×１０６和εＳｃ＝３．５９×１０＿５Ｌ·ｍｏｌˉ１·ｃｍˉ１，铈和钪服从比耳定律的浓度范围分别为０～０．８μｇ／２５ｍｌ和０～２．０μｇ／２５ｍｌ，测定极限分别为１．３ｎｇＣｅ／ｍｌ（ｎ＝１０）和３．０ｎｇＳｃ／ｍｌ（ｎ＝７），对于０．０２μｇＣｅ／ｍｌ或０．０４μｇＳｃ／ｍｌ测定的相对标准偏差分别为２．７％（ｎ＝９）和２．８％（ｎ＝１０），离子缔合物的摩尔比分别为Ｃｅ：Ｍｏ：ＮＢ＝１：６：４和Ｓｃ：Ｍｏ：ＮＢ＝１：１２：３。本法用于地质标样分析，结果满意。     

聚马来酸酐的溶解性及与其他树脂相容性研究

聚马来酸酐是聚烯烃、氯化聚烯烃用马来酸酐接枝改性的副产物。研究其基础物性对接枝反应产物的使用和分离具有一定的价值。本文测定了聚马来酸酐在 2 8种溶剂中的溶解性能 ,表明该物质能完全溶解在酮类、醇类、醚类、酯类等极性溶剂中 ,而在非极性的脂肪烃、芳烃类溶剂中不溶。用特性黏度法测定了该聚合物的溶解度参数为 2 2 .10 (J·cm-3 ) 1/2 。用共溶剂法研究了聚马来酸酐与其他树脂的相容性 ,发现该聚合物可以和氨基树脂 ,醇酸树脂 ,聚氨酯 ,丙烯酸树脂等完全相容。     

反气相色谱法研究增塑剂-探针分子的热力学性能

利用凝胶色谱(GPC)、热重分析(TGA)、表面张力仪和差示扫描量热(DSC)法等对增塑剂环烷油的分子结构及其基本性能进行了表征。以不同种类的溶剂作为探针分子,采用反气相色谱(IGC)法对增塑剂的热力学性能进行了研究。结果表明:在试验温度(50～80℃)范围内,正戊烷、正己烷、正庚烷、环己烷、氯仿、苯和乙醚是环烷油的良溶剂,甲醇和丙酮是环烷油的不良溶剂;IGC法测得随着温度的升高,环烷油的溶度参数从50℃的13.94(J/cm3)1/2逐渐降至80℃的13.21(J/cm3)1/2;利用相互作用参数与温度的关系,采用外推法可得到25℃时环烷油的溶度参数为14.38(J/cm3)1/2,这与14.50(J/cm3)1/2(根据表面张力-溶度参数关系式计算而得)基本一致。     

Cohesive energy densities of poly(di-n-alkyl itaconates)

The solubility parameters of the first ten members of the homologous series of poly(di-n-alkyl itaconates) were determined from limiting viscosity numbers in various organic solvents, differing in structure, polarity and hydrogen bonding capacity. Numerical values from 9.58 to 8.10 (cal/cm³)^1/2 were obtained independently from measurements in hydrocarbon and oxygen containing solvents, close to solubility parameters calculated from polymer densities and molar attraction constants. The values obtained reflects the increasing paraffinic character within the series and can be correlated to solubility parameters published in the literature for structurally similar poly(alkyl acrylates) and poly(alkyl methacrylates).     

Comparison of various solvents for determination of intrinsic viscosity and viscometric constants for cellulose

Different solvents used to determine the intrinsic viscosity and the viscometic constants, a and K, published in the literature for cellulose, were compared. The various parameters affecting the viscometric constants were also evaluated. The main conclusions obtained from the experimental data available in the literature are that (1) the intrinsic viscosities in various solvents are ordered as follows: [η]_LiCl/DMAc > [η]_NH3/NH4SCN ≥ [η]_FeTNa > [η]_CED > [η]_Cadoxen > [η]_Cuoxam; (2) the reported intrinsic viscosities and molecular weights for cellulose are lower than the true value due to degradation of cellulose in the solvents; (3) the rate of degradation was the smallest in LiCl/DMAc and NH₃/NH₄SCN, moderate in cadoexn and FeTNa, and the highest in CED and cuoxam; (4) the plot of log K versus exponent a was linear and inversely related; (5) the curve was used for estimation of the constant K for cellulose in a solvent (NH3/NH4SCN) with a known exponent a; and (6) among various reported solvents, LiCl/DMAc and NH₃/NH₄SCN are advantageous over other solvents because of a complete dissolution of the polymer with a negligible reduction in its intrinsic viscosity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2189–2193, 2002     

Spontaneous fracture of coal

Examples of the spontaneous fracture of various United States coals using several different solvents with solubility parameters in the range 9–15 (cal/cm³)^1/2 [18.5–30.7 (J/cm³)^1/2] were used to identify a swelling—fracture relation which predicts the final maximum particle size of the reacted coal. The effects of liquid ammonia were of particular concern. The model appears consistent with the observed effects of various liquids, including water, on various coals in bench and pilot-plant scale. A distinct advantage for the unique separation of pyrite or other mineral matter was not observed.     

Charge transfer copolymerization and properties of isopropyl methacrylate with acrylonitrile and methacrylonitrile

Isopropyl methacrylate (IPMA) with Acrylonitrile (AN) and Methacrylonitrile (MAN) copolymers of different copositions were prepared at 60°C and 80°C, respectively, using a mixture of n-Butylamine (nBA) and carbon tetrachloride (CCl₄) in dimethyl sulphoxide (DMSO) as a charge transfer (CT) initiator. The percentage composition of the copolymers was established by elemental analysis. The copolymerization reactivity ratios were computed by the Kelen–Tudos method. In both the systems, IPMA was found to be more reactive; the copolymers sequence was random in nature. The copolymers were characterized by IR, ¹H-NMR, ¹³C-NMR spectroscopy and intrinsic viscosity measurements in dimethyl formamide (DMF) at 30±0.1°C. The thermal behavior of the AN-IPMA copolymers was studied by thermogravimetry (TG) in air. The thermal stability increased, with increasing AN content in the copolymer chain. The solubility parameter of AN-IPMA copolymer was evaluated by studying the intrinsic viscosity in different solvents. The solubility parameter of the copolymer was found to be 9.7 (cal/cc)^1/2.     

Validity of the swelling method for the determination of the interaction parameter

By selecting solvents with a very weakly concentration-dependent interaction parameter χ with poly(dimethylsiloxane) (PDMS) and using experimental values of the elastic modulus of dry, end-linked PDMS networks, the Flory-Rehner theory and the phantom network assumption we obtained good agreement between the values of χ from equilibrium swelling and those obtained from intrinsic viscosity measurements on solutions of linear chains. The solvents used were 2,3-dimethylpentane and 2,2,4-trimethylpentane at 25°C.     

Swelling characteristics of NR/PU block copolymers and the effect of NCO/OH ratio on swelling behaviour

A series of (NR/PU) block copolymers (BCs) was prepared from toluene diisocyanate (TDI), 1,3-butane diol (1,3-BDO), and hydroxyl-terminated liquid natural rubber (HTNR), by solution polymerisation. The swelling characteristics of the BCs were investigated. Diffusion profile in various solvents and the sorption kinetics were studied. Arrhenius and thermodynamic parameters were evaluated from the diffusion data. Finally, the influence of NCO/OH ratio on the swelling behaviour was also studied. The equilibrium sorption value (Q_∞) decreased with increasing NCO/OH ratio for all the BCs. The samples have higher uptake of solvents with solubility parameter within a small range centred about 9 (cal/cm³)^1/2. Highly polar and non-polar solvents show minimum uptake. It was observed that polarity factor predominates in the solvent transport through the present block copolymer systems. The sorption behavior is also found to vary with the NCO/OH ratio employed in the preparation of polyurethane (PU) oligomers.     

Thermal Conductivity of Sintered UO, and Al2O3 at High Temperatures

The thermal conductivities of sintered Al₂O₃ and UO₂ were measured in the ranges 400° to 1700°C and 300° to 2100°C respectively. The conductivity values for Al₂O₃ agreed with those reported previously at all temperatures investigated. The conductivity of UO, decreased with increasing temperature to a minimum of 0.0050 cal per cm sec °C at about 1400°C, and then increased with increasing temperature to 0.0105 cal per cm sec °C at 2100°C.     

氯化聚丙烯溶度参数的研究

氯化聚丙烯是对聚丙烯材料有很好的粘结力 ,为了进行基础的应用研究 ,用浊度法对其溶度参数进行了测定 ,得到其溶度参数为 16 .72～ 2 1.15 (J/cm3 ) 1/ 2 。氯化聚丙烯溶解性能实验表明 :氯化聚丙烯属于弱极性物质。在溶度参数接近时 ,一般弱极性溶剂为良溶剂 ,中等极性溶剂为微溶溶剂。还用三维溶度参数对CPP的溶解性能进行了讨论。