Analyses of non-aqueous reactive polymer insulation layer in high geothermal tunnel

The scenario of geothermal tunnel is commonly observed around the world,and increases with the new constructions in the long and deep tunnels,for example in China.Tunnel insulation is generally divided into active and passive insulation.In passive insulation,it is an effective way to set low thermal con-ductivity materials as the thermal insulation layer as the choice of insulation material mainly depends on the thermal conductivity.Polymer is a kind of material with good geothermal performance,but there are relatively few studies.In this context,the transient plane source(TPS)method was used to measure the thermal conductivity of the developed polymer.Then,the temperature field of the high geothermal tunnel insulated by the non-aqueous reactive polymer layer was simulated.With the parametric analysis results,the suggestions for the tunnel layers were proposed accordingly.It revealed that the thermal conductivity of polymer first increases and then decreases with temperature.There are two rising sec-tions(?40e10?C and 20e90?C),one flat section(10e20?C)and one descending section(>90?C).It is observed the thermal conductivity of polymer increases with increase of the density of insulation layer and the density,and the thermal conductivity decreases when exposed to high temperatures.The temperature of the surrounding rocks increases with increase of the thermal conductivity and the thickness of polymer.Finally,a more economical thickness(5 cm)was proposed.Based on the parametric study,a thermal insulation layer with thermal conductivity less than 0.045 W/(m K),thickness of 5 cm and a density less than 0.12 g/cm 3 is suggested for practice.

EQUILIBRIUM AND KINETIC ADSORPTION OF A REACTIVE BLACK KNB DYE ON POLYDIVINYLBENZENE AND STYRENE-DIVINYLBENZENE COPOLYMER RESINS

In this study, two polymeric resins with different pore sizes were synthesized to study comparative adsorption of reactive black KNB dye. Styrene-divinylbenzene copolymer resin NG-8 has an average pore size of 3.82 nm, about half of that of polydivinylbenzene resin NG-7 （6.90 nm）. NG-8 also has a surface acidity about 4 times that of NG-7, resulting in a much more negative surface of the former resin as compared to the latter at pH 6.05. Equilibrium adsorption of KNB was significantly influenced by the surface functionality of the resins, as evidenced by the observations that NG-8 adsorbed constantly less KNB than NG-7 and that the presence of CaCl2 enhanced the adsorption by both resins. The intra-particle diffusion appears to be the primary rate-limiting process. While the pores of both resins are accessible to KNB, the slower adsorption by NG-8 than by NG-7 suggests that the smaller pores of NG-8 further retard the intra-particle diffusion of KNB.

Influence of Reactive Diluent on UV-curing of AcrylateTerminated Hyperbranched Polymers

A Aeries of hydroxylic hyperbranched polymers were derived from 2,2-bis(methylol) propionic acid and tris(methylol) propane reacted with acrylic acid to various extents. The obtained acrylated hyperbranched polymers alone or with a monofunctional diluent, isobornylene acrylate(IBOA) were further cured by UV radiation. The cured films based on the modified polymers alone all demonstrated poor mechanical properties due to their high network densities and low moving ability of polymer chains. For the composite systems, the cured films demonstrated improved mechanical properties due to the low network densities and high chain moving ability. With more IBOA included in the systems, acrylate groups can react to a higher extent during the curing process.

Porous polymer microsphere functionalized with benzimidazolium based ionic liquids as effective solid catalysts for esterification

To prepare polymer supported ionic liquids(PSILs)as effective catalysts for esterification,the free radical suspension copolymerization of vinylbenzyl chloride(VBC,monomer),styrene(St,monomer)and divinylbenzene(DVB,crosslinker)with the addition of n-heptane(porogen)was carried out for the fabrication of the porous polymer(PVD)microsphere as support,followed by the immobilization of sulfonic acid-functionalized ionic liquids by the successive treatment of benzimidazole(BIm),1,3-propane sultone and sulfuric acid(H2SO4)or trifluoromethanesulfonic acid(CF3SO3H).The effects of the compositions of DVB and n-heptane on the internal structure of the polymer supports were investigated,and it was found that the support with 40 wt%DVB and 60 wt%n-heptane(with relative to the monomer)could endow the final PSILs with the relatively optimal catalytic performance.The preliminary experiment in the batch reactor indicated that PSILs herein exhibited higher catalytic activities than commercial Amberlyst 46 resin for the esterification of propanoic acid(PROAc)with n-propanol(PROOH).Consequently,the optimal PSILs catalyst,PVD-[Bim-SO3H]HSO4,was selected for further study in the batch reactive distillation column because of low cost and its ease of preparation.The yield of propyl ropionate(PROPRO)could reach up to 97.78%at the optimized conditions of PROOH/PROAc molar ratio(2:1)and catalyst dosage(2.0 wt%).The investigation of the reaction kinetic manifested that the calculated results of second order pseudo-homogeneous kinetic model were in good agreement with experimental values.The pre-exponential factor and activation energy were 4.12×107 L·mol-1·min-1 and 60.57 k J·mol-1,respectively.It is worth noting that the PSILs catalyst could be simply recovered and reused with relatively satisfactory decrease in the catalytic activity,which made it an environmental friendly and promising catalyst in the industrial application.

SYNTHESIS OF NEW HIGH MOLECULAR WEIGHT AND REACTIVE LADDERLIKE POLYSILSESQUIOXANES

Ladderlike polychloropropylsilsesquioxane (CP-T) was first synthesized by 'stepwise coupling polymerization'. The molecular weight of CP-T is as high as 1.7 x 10(5). It is a tough, elastic reactive ladderlike polymer and has good heat-resistant and adhesive properties. CP-T can further react with many nucleophilic reagents to generate new ladderlike reactive polysilsesquioxanes, which can be used as potential precursors in the synthesis of functional ladderlike polymers.

A New Monodisperse Reactive Resin with Active Groups on the Particle Surface

A novel reactive resin as active support was synthesized by an improved method based on seed swelling and surface coating polymerization. The resin is monosized beads with inner nucleus of cross-linked polymer and surface layer of copolymer containing epoxy groups. The physico-chemical structures of beads were characterized.

PREPARATION OF FUNCTIONAL MATERIALS BY BLENDING COPOLYESTERS WITH PVA AND METAL COMPLEX FORMATION OF POLYMER BLENDS

Copolyesters having secondary and tertiary amine salt groups in the main and side chains are prepared by chemoselective polymerization. These copolyesters are soluble in a 10% aqueous solution of poly(vinyl alcohol) (PVA) at 90 degree C and act as plasticizer in the blend films cast from the solution. Only a glass transition temperature is observed for all these blends indicating the formation of compatible blends from these polyesters with PVA. These blends exhibit manifold characteristics such as ionic conductivity, complex formation with metal ions, absorption of moisture and color changes. The electric conductivity of the copolyesters and blends is in the range of 10** minus **6 Scm** minus **1. The blends with PVA forms complexes with Cu**2** plus and Co**2** plus . The coordination structure with two chelate rings is suggested for these polymer blend/metal complexes. (Author abstract) 10 Refs.

Si-GDP结构和力学性能的反应分子动力学模拟

构建了硅掺杂辉光放电聚合物(Si-GDP)模型,采用反应力场分子动力学模拟(ReaxFF MD)探讨了硅含量、碳氢比及密度对其杂化碳键合与力学性能的影响。研究结果表明:随着硅含量增加,聚合物中sp^(3)C含量增加,趋向于形成一个大分子,同时小分子种类和数目减少,促进了碳硅原子成键并抑制端基CH_(3)生成,进而提高材料力学性能;随着氢含量的增加,sp^(3)C和端基CH_(3)比例增加,生成的端基CH_(3)降低了分子间交联程度,进而降低了材料力学性能,而分子基团数目变化不明显;随着密度的提升,聚合物中sp^(2)C比例提升明显,sp^(3)C比例有少量提升,分子基团数目变化不大,密度主要通过提升sp^(2)C比例提升材料力学性能。研究结果为评估和理解硅掺杂辉光放电聚合物的结构和力学性能提供了新的视角和方法。

Polarization engineering in porous organic polymers for charge separation efficiency and its applications in photocatalytic aerobic oxidations

Photocatalytic aerobic oxidation reactions are largely governed by the efficiency of charge separation and subsequent reactive oxygen species(ROS) generation. Herein, we report a polarization engineering strategy to promote the charge separation and ROS generation efficiency by substituting the benzene unit with furan/thiophene in porous organic polymers(POPs). Benefiting from the extent of local polarization, the thiophene-containing POP(JNU-218) exhibits the best photocatalytic performance in aerobic oxidation reactions, with a yield much higher than those for the furan-containing POP(JNU-217) and the benzenecontaining POP(JNU-216). Experimental studies and theoretical calculations reveal that the increase of local polarization can indeed reduce the exciton binding energy, and therefore facilitate the separation of electron-hole pairs. This work demonstrates a viable strategy to tune charge separation and ROS generation efficiency by modulating the dipole moments of the building blocks in porous polymeric organic semiconductors.

矿用高分子材料液体组分中游离甲醛测量不确定度评定

对煤矿用反应型高分子材料液体组分中游离甲醛测量进行不确定度评定,可为试验室游离甲醛含量测定结果质量控制及检测报告的合理性提供科学依据。按照现行标准AQ 1116—2020及GB 18583—2008对装修材料胶黏剂中有害物质限量的规定,采用乙酰丙酮分光光度法测定煤矿用反应型高分子材料液体组分中游离甲醛含量,并对测量结果的不确定度进行评定。矿用反应型高分子材料液体组分中游离甲醛含量在95%置信概率(k=2)下的测定结果为(0.0568±0.0019)g/kg。结果表明,影响测量不确定度的主要因素包括称量样品、样品吸光度测量重复性、标准曲线绘制以及移取和定容溶液过程等引入的相对标准不确定度,而标准曲线绘制、移取和定容溶液过程是引起测量不确定度的主要因素。为了提升试验室测量结果的准确性,关键在于规范玻璃仪器的使用以及准确进行精细化标准溶液吸光度测试。

Reactive ion etching of poly(vinylidene fluoride-trifluoroethylene) copolymer for flexible piezoelectric devices

A microfabrication process for poly(vinylidene fluoride-trifluoroethylene)(P(VDF-TrFE)) based flexible piezoelectric devices is proposed using heat controlled spin coating and reactive ion etching(RIE) techniques.Dry etching of P(VDF-TrFE) in CF 4 +O2 plasma is found to be more effective than that using SF 6 +O2 or Ar+O2 feed gas with the same radiofrequency power and pressure conditions.A maximum etching rate of 400 nm/min is obtained using the CF 4 +O2 plasma with an oxygen concentration of 60% at an antenna power of 200 W and a platen power of 20 W.The oxygen atoms and fluorine atoms are found to be responsible for the chemical etching process.Microstructuring of P(VDF-TrFE) with a feature size of 10 m is achieved and the patterned films show a high remanent polarization of 63.6mC/m 2.

液体再生橡胶作为反应型高分子增塑剂的应用研究

采用同向双螺杆挤出机制备液体再生橡胶(LRR),并将其作为反应型高分子增塑剂用于天然橡胶(NR)胶料,研究其应用效果。结果表明:LRR的溶胶含量高,粘度小,其具有可再交联的特性;LRR具有一定的增塑作用,与NR相容性好,混炼胶的丙酮抽出物含量小,其难喷霜;与环保芳烃油相比,LRR在NR胶料硫化过程中参与交联反应,采用LRR的硫化胶具有更大的硬度、定伸应力和拉伸强度,表明LRR起到了反应型高分子增塑剂的作用。

考虑电网辅助服务的分布式能源聚合体优化方法

分布式能源个体一般无法直接参与电力市场交易或提供电网辅助服务,这可以通过分布式能源聚合来解决。在多能源类型、多交易市场及多服务基础上,提出一种新的分布式能源聚合体优化方法,该方法分为一级、二级、三级3个阶段的优化。首先,一级优化中使用了线性化技术来克服聚合体跨时空调度问题的非凸性,并将问题转换成混合整数线性规划问题,得出日前机组组合方案;其次,二级优化中基于一级优化给出的机组组合方案并使用最优潮流方程的二阶锥凸松弛求解经济调度问题以获得节点电压和功率流;然后,在三级优化中对偏离二级优化设定点进行惩罚,使三级优化接近系统最佳运行点,同时具有较短的规划范围;最后,在案例研究中将优化方法应用于一个包含电解制氢、风力发电及光伏发电等多能源聚合体模型。测试结果表明:所提出方法在电网辅助服务支持和聚合体灵活性增强方面的优势,并以最大限度增加运营收益,证明所提方法的有效性。

Z型全氟聚醚的结构表征

具有功能性端基的全氟聚醚具有优异的化学稳定性及较强的加工可塑性,被广泛用于航天航空、电子、化工等领域。在其制备及应用过程中,基于核磁共振技术的结构表征和解析至关重要。然而由于全氟聚醚及其活性化合物的结构复杂、分子量大且分布较宽,因此在核磁测试中存在制样难、主链骨架结构和端基难以分辨和归属等问题,进而影响对全氟聚醚的定性定量分析。针对Z型惰性及活性全氟聚醚的结构解析,系统考察了不同种类氘代试剂和含氟助溶剂的复配、样品浓度、测试条件等因素的影响,探索得到较优的核磁样品制备条件;进一步分析了Z型全氟聚醚混合物的氟谱,确定了全氟聚醚的主链结构和端基的归属;利用端基分析法计算得到分子量及聚合度、两组分全氟聚醚混合物组成。

煤矿反应型高分子材料反应温度自动测试可靠性研究

为了研究反应型高分子材料反应温度自动测定装置的可靠性,选取五种煤矿用反应型高分子材料,比较装置自动测定和手动测定的最高反应温度,并通过F检验和t检验验证两种结果的精密度和平均值是否存在显著性差异。结果表明:自动测试结果与手动测试结果的精密度和平均值均不存在显著性差异,两种方法的精密度、正确度均满足要求,说明该自动测定装置测试结果可靠,可用于煤矿反应型高分子材料最高反应温度的测定。

Excellent Compatibilization Effect of a Dual Reactive Compatibilizer on the Immiscible MVQ/PP Blends

Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and thus it is especially suitable in bio-safety areas and wearable electronic devices, etc. Nevertheless, the compatibility between MVQ and PP phases is poor. A big challenge on the compatibilization of MVQ/PP blends is that neither MVQ nor PP contains any reactive groups. In this study, a dual reactive compatibilizer composed of ethylenemethyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA) and maleic anhydride grafted polypropylene (PP-g-MAH) was designed for the compatibilization of MVQ/PP blends. During melt blending, a copolymer compatibilizer at the MVQ/PP interface can be formed because of the in situ reaction between EMA-co-GMA and PP-g-MAH. The thermodynamic predict of its compatibilization effect through calculating the spreading coefficient of the in situ formed copolymer indicates that it can well compatibilize MVQ/PP blends. The experimental results show that under the GMA/MAH molar ratio of 0.5/1, the interface thickness largely increase from 102 nm for non-compatibilized blend to 406 nm, and the average size of MVQ dispersed phase largely decreases from 2.3 µm to 0.36 µm, the Tg of the two phases shifts toward each other, the mixing torque and mechanical properties of the blend are increased, all indicating its good compatibilization effect. This study provides a good compatibilizing method for immiscible MVQ/PP blends with no reactive groups in both components for the preparation of high performance MVQ/PP TPVs.

光催化复合膜研究进展

随工业扩张和人口迅增,水污染日益严重。光催化技术由于对污染物降解的高效性和彻底性而成为研究热点。在光催化技术发展中,最重要是对催化剂的回收。催化剂没回收好,很有可能造成二次污染。膜回收技术因其低成本、操作简单、可循环利用等优点而备受关注。本文对目前广泛使用的聚合物光催化膜、陶瓷基光催化膜和金属基光催化膜的研究进行了综合评述,阐述了各类光催化复合膜的优缺点并对其应用进行了展望。

活化过氧化氢用于甲苯光催化氧化的3-溴噻吩基共轭有机聚合物

以3-溴噻吩单体和粉体氧化铜为原料,采用FeCl3氧化偶联的方法制备负载氧化铜的聚(3-溴噻吩)光催化剂(thBr-CuO)。负载氧化铜后,thBr-CuO的光吸收能力与光生载流子利用率得到明显改善。可见光下,thBr-CuO催化甲苯转化的速率达到0.69 mmol/(g·h),高于初始聚(3-溴噻吩)。猝灭实验与香豆素荧光探针法证实该光催化过程中的主要活性物种为光生空穴与羟基自由基。通过光生电子-空穴对的有效分离以及对过氧化氢的高效利用,3-溴噻吩基共轭有机聚合物的光催化性能显著提升。

活性染料印花糊料研究进展

织物印花作为一种高效且方便的织物局部染色方法,已经广泛用于棉织物和化纤织物染色。而印花糊料作为重要的染色介质,其对印花织物的得色量、图案轮廓清晰度、手感等具有决定性的影响。重点介绍目前常用的印花糊料,包括天然高分子糊料、合成高分子糊料和无机矿物质糊料,最后总结了目前印花糊料的研究进展和方向。

反应挤出在聚合物共混改性中的应用与进展

综述了反应挤出技术发展概况 ,反应挤出实施要点 ,分析了反应挤出共混改性效果的影响因素 。