高吸水性防灭火材料的研究与应用

高吸水性材料是可吸收自重几百倍甚至几千倍水的新型功能高分子材料，广泛应用于农业、卫生、医药、建筑等方面。根据高吸水性防灭火材料添加剂种类的不同对材料进行系统分类，详细介绍了材料的防灭火原理，总结了高吸水性防灭火材料的吸水保水性、稳定性、可燃烧性、可生物降解性等性能的研究，并简要概括了其国内外的研究和应用现状。     

绿色高吸水性树脂的研究进展

综述了可生物降解的绿色高吸水性树脂的研究发展,讨论了该类高分子树脂的结构要求。主要介绍了近年来淀粉、纤维素、海藻酸钠、甲壳类和蛋白质等天然高分子改性吸水性材料,聚氨基酸类吸水性树脂及丙烯酸合成类高吸水性树脂等的吸水性能和生物降解特性,并对绿色高吸水性树脂的研究发展方向和应用前景进行了展望。     

改性高吸水性聚合物的研究进展

综述了高吸水性聚合物的吸水机理,重点介绍了提高高吸水性聚合物的耐盐性、吸水速率、凝胶强度及增大耐候性的各种方法,最后指出,高吸水性聚合物应该向材料复合化、可生物降解性、注重基础理论研究等方向发展.     

FR-1阻化泡沫材料的研发及在煤矿防灭火中的应用

煤矿火灾是煤矿生产中的主要自然灾害之一，并多表现为煤层自然发火灾害。为了更好地解决煤矿采空区高位空间的防灭火难题，我矿引进并使用阻化泡沫防灭火技术工艺及材料，并成功应用在煤矿防灭火工作中。本文介绍了阻化泡沫防灭火技术工艺及材料的研发过程、材料性能、应用效果等，可供有关单位借鉴。     

新型喷涂材料推广应用

针对巷道密闭墙喷涂隔风的技术难题,提出了采用复合瑞米浆体材料进行喷涂防灭火的新技术。本文研究了瑞米材料的最佳配方,并介绍了实际情况。结果表明,喷涂隔风效果优越,是适于矿井喷浆防灭火的优良材料。     

可生物降解性高吸水材料的研究状况

综述了可生物降解性高吸水性材料的研究状况,重点介绍了淀粉类、纤维素类、海藻酸类、壳聚糖类等天然高分子类以及聚乳酸类、聚氨基酸类和微生物合成类高吸水材料的开发和研究,并对其未来发展作出展望.     

煤矿三元复合胶体防灭火材料的制备与性能研究

用快硬硫铝酸盐水泥、大掺量粉煤灰、水玻璃,外加悬浮剂,一步混合法制备了三元复合胶体防灭火材料,研究了该材料的凝结时间、抗压强度和阻化性能,观察了微观形貌,探讨了胶凝机理。结果表明,材料胶结体的初凝时间在1~30 min范围内可控,并具有良好的早期抗压强度;60℃阻化率达90%,70℃达80%,80℃不低于75%;胶结体内部存在大量絮凝状的C-S-H凝胶,且与粉煤灰胶连,结构密实。工业实验表明该防灭火材料具有良好的防灭火效果。     

天然高分子系高吸水性树脂的研究

近年来我国对于高吸水性树脂的需求量逐年增加,采用天然高分子材料如淀粉、纤维素和壳聚糖等作为原料与亲水性乙烯基单体进行接枝共聚制备的高吸水性树脂,产品性能优异,成本低廉,污染少,日益受到重视。本文介绍了此类天然高分子材料制备高吸水性树脂的品种发展。     

我国煤矿矿井防灭火技术研究综述

总结了近年来我国在煤矿矿井火灾预测预报理论及方法、矿井煤炭自燃火源区域探测方法、矿井防灭火技术、外源火灾检测及防治和矿井防灭火决策系统等方面的研究和应用进展,分析了我国在煤矿矿井防灭火技术研究和应用中存在的问题。     

利用秸秆纤维制备高吸水材料的研究

以麦秸秆为原料,通过添加丙烯酸类单体和蒙脱土,采用水溶液聚合法制备了高吸水性材料.考察了麦秸秆的预处理方式(酸处理、碱处理和醚化处理)及交联剂用量时高吸水性材料性能的影响,以红外光谱和扫描电镜表征高吸水性材料的结构.研究结果表明,采用醚化方式处理的麦秸秆制备的高吸水材料性能最好,随交联剂用量的增加,材料的吸水性呈先增大后减小的趋势.丙烯酸类单体成功发生了接枝聚合反应,高吸水材料呈现典型的三维网络结构.     

高吸水性聚合物性能指标与测试方法

高吸水性聚合物是一种能够大量吸收水溶液的新颖的高分子材料。本文对高吸水性聚合物的性能指标与测试方法作了简明的介绍。     

Chloride migration in concrete with superabsorbent polymers

Superabsorbent polymers (SAP) can be used as a means for internal curing of concrete. In the present study, the development of transport properties of concrete with SAP is investigated. The chloride migration coefficient according to NT BUILD 492 is used as a measure of this. Twenty concrete mixtures are tested 7, 14, and 28 days after casting. The development of degree of hydration is followed for 20 corresponding paste mixtures.Both when SAP is added with extra water to compensate the SAP water absorption in fresh concrete and without extra water, the internal curing water held by SAP may contribute to increase the degree of hydration. No matter if SAP is added with or without extra water, it appears that the so-called gel space ratio can be used as a key parameter to link age and mixture proportions (water-to-cement ratio and SAP dosage) to the resulting chloride migration coefficient; the higher the volume of gel solid relative to the space available for it, the lower the chloride migration coefficient, because the pore system becomes more tortuous and the porosity becomes less.     

A review of characterisation methods for superabsorbent polymer (SAP) samples to be used in cement-based construction materials: report of the RILEM TC 260-RSC

Superabsorbent polymers (SAPs) have proven to be a very promising admixture which can positively influence various properties of cement-based materials. SAP samples intended for such use should be pre-tested with respect to their absorptivity as well as their kinetics of ab- and desorption prior to implementation in concrete or mortar. This not only reduces workloads in concrete laboratories in pre-testing modified cement-based mixtures but in fact discloses essentials of the eventual performance of the SAP in concrete and other cementitious materials. The review at hand outlines fundamentals of the thermodynamics of polymer chemistry as a basis for the sorptivity tests. The importance of the ionic composition of the test liquids and the interplay among expansive (swelling) and collapse-causing chemical forces in the hydrogel network are highlighted. Methods of free sorptivity testing in adequate saline solutions as well as absorbency determined subject to the application of external forces are summarised. Advantages and drawbacks of these methods are discussed, including a validation of anticipatory evaluations of SAPs’ performance as admixtures in cement-based building materials. Apart from sorptivity pre-tests several methods of instrumental analytics for the chemical characterisation of SAP samples are drawn up, which represent standard approaches of polymer-chemical analytics.     

聚丙烯酸系超吸水纤维的研究进展及应用

超吸水纤维(SAF)是一种具有强吸湿、放湿能力的功能性高分子纤维。它的问世弥补了粉末、颗粒状高吸水树脂作为吸水材料在加工成型等方面上的不足,在某些领域上可替代超吸水纤维,获得更优的性能。而丙烯酸类超吸水纤维是以丙烯酸为原料制得,原料价廉易得,产品吸水率高且吸水速率快,是近年来的研发热点。为此,对丙烯酸类超吸水纤维的制备方式及其实际应用进行了综述。     

蔗糖基聚合物的研究进展

以蔗糖为原料可以制备安全无毒、可生物降解、高吸收性凝胶聚合物,聚合的途径目前有化学法和酶法,这些材料可用于普通的水吸收剂、水净化辅助剂和生物医学材料,还可作为植物生长调节剂、果蔬常温保鲜剂应用于农业生产。本文综述了近十年国内外蔗糖基聚合物的研究进展及其应用前景,并对蔗糖基聚合物的结构特点、制备方法作了较为详细的论述。     

基于SAP吸水膨胀橡胶的耐温耐盐性能

以反相悬浮聚合法合成P(AANa/AMPS/DMDAAC)两性共聚高吸水树脂(SAP),并引发溶胀在SAP中的丙烯酸丁酯和丙烯酸进行原位共聚合,制备疏水改性高吸水树脂。将丁腈橡胶、改性高吸水树脂、补强剂和其他助剂借助混炼机混炼均匀,在硫化成型机上高温硫化制备吸水膨胀橡胶(WSR)。研究盐溶液种类、盐溶液浓度以及环境温度对WSR的质量吸水膨胀倍率的影响,并对吸水后的WSR进行热重分析。结果表明:盐溶液中阳离子浓度越大,化合价越高,对WSR吸水性能影响越明显,吸液膨胀倍率越小;在对WSR进行一系列不同温度下的吸液性能研究时发现,WSR在120℃具有较好的吸水膨胀性能。在环境温度达到175℃时,WSR达到失水平衡。     

Protonation‐Assisted Exfoliation of N‐Containing 2D Conjugated Polymers

Ultrathin 2D conjugated polymer nanosheets are an emerging class of photocatalysts for solar‐to‐chemical energy conversion. Until now, the majority of ultrathin 2D polymer photocatalysts are produced through exfoliation of layered polymers. Unfortunately, it still remains a great challenge to exfoliate layered polymers into ultrathin nanosheets with high yields. In this work, a liquid‐phase protonation‐assisted exfoliation is demonstrated to enable remarkably improved exfoliation yields of various 2D N‐containing conjugated polymers such as g‐C₃N₄, C₂N, and aza‐CMP. The exfoliation yields are only 2–15% in pure water whereas they can be substantially improved to 41–56% in 12 m HCl. The exfoliated ultrathin nanosheets possess average thicknesses less than 5 nm and can be easily dispersed in aqueous solutions. More importantly, the exfoliated nanosheets exhibit significantly enhanced photocatalytic activity toward photocatalytic water splitting compared to their bulk counterparts. Further characterizations and computational calculations reveal that protonation of the heterocyclic nitrogen sites in the conjugated polymer frameworks can lead to strong hydrogen bonding between the polymer surfaces and water molecules, resulting in facilitated exfoliation of polymers into the liquid phase. This study unveils an important protocol toward producing ultrathin 2D N‐containing conjugated polymer nanosheets for future solar energy conversion.     

Design of novel polymeric adsorbents for metal ion removal from water using computer-aided molecular design

Heavy metals in drinking water act as contaminants that can cause serious health problems. These metal ions in drinking water are generally removed using cation exchange resins that are used as adsorbents. Generally, chelating resins with limited adsorption capacity are commercially available. Manufacturing novel resin polymers with enhanced adsorption capacity of metal ion requires ample experimental efforts that are expensive as well as time consuming. To overcome these difficulties, application of computer-aided molecular design (CAMD) will be an efficient way to develop novel chelating resin polymers. In this paper, CAMD based on group contribution method (GCM) has been used to design novel resins with enhanced adsorption capability of removing heavy metal ions from water. A polymer consists of multiple monomer units that repeat in a polymer chain. Each repeat unit of the polymer can be subdivided into different structural and functional groups. The adsorption mechanism of heavy metals on resin depends on the difference between activities in adsorbents and the bulk fluid phase. The contribution of the functional groups in the adsorption process is found by estimating the activity coefficient of heavy metal in the solid phase and bulk phase using a modified version of the UNIFAC GCM. The interaction parameters of the functional groups are first determined and then they are used in a combinatorial optimization method for CAMD of novel resin polymers. In this work, designs of novel resin polymers for the removal of Cu ions from drinking water are used as a case study. The proposed new polymer resin has an order of magnitude higher adsorption capacity compared to conventional resin used for the same purpose.     

磷酰胆碱共聚物的合成及膜的生物相容性

为了研究磷酰胆碱类聚合物的生物相容性,以偶氮二异丁腈(AIBN)为引发剂,采用自由基聚合制备了系列2-甲基丙烯酰氧乙基磷酰胆碱(MPC)与甲基丙烯酸丁酯(BMA)、甲基丙烯酸异辛酯(EHMA)的共聚物PMB、PMEH.用红外光谱、元素分析、核磁共振等方法对其结构进行了表征并探讨了其在不同溶剂中的溶解性,为该类物质的提纯提供依据;通过溶剂挥发法制备了共聚物薄膜,血小板黏附实验显示,含有MPC的聚合物薄膜比不含MPC的聚合物薄膜有更好的血液相容性;溶胀度测试显示MPC聚合物薄膜有非常好的吸收水的能力,且平衡含水量(EWC)会随着MPC在聚合物薄膜中含量的增加而增加,当MPC在PMB20中的摩尔含量为18%时,平衡含水量可以达到47%,这是磷酰胆碱类聚合物薄膜具有优良生物相容性的原因之一.     

Synthesis and polymerization of substituted ammonium sulfonate monomers for advanced materials applications

Sulfonated polymers have found use as ion-exchange membranes for use in fuel cells, water purification, electroactive devices, and inorganic materials templating and synthesis. Improving the materials for these applications and opening up new applications requires the ability to synthesis targeted or more complex sulfonated polymers, which includes tailoring the chemistry (copolymerization across a wider range of solubility) and/or polymer architecture (block, graft, nanoparticle). This article will summarize the recent work using sulfonated monomers with substituted ammonium counterions as a versatile route for enabling this goal. Two main benefits of these monomers are as follows. First, they are useful for preparing amphiphilic copolymers, which is a challenge using traditional acidic or alkali salt forms of sulfonated monomers. Second, sulfonated polymers with substituted ammonium counterions are useful polymers for obtaining unique material properties, such as organo-gelation of low polarity solvents or obtaining ionic liquid polymers for the fabrication of solid polymer electrolytes.