Reactive Energetic Plasticizers for Energetic Polyurethane Binders Prepared via Simultaneous Huisgen Azide‐Alkyne Cycloaddition and Polyurethane Reaction

Reactive energetic plasticizers (REPs) for use in glycidyl azido polymer (GAP) based polyurethane (PU) energetic binders were investigated. These REPs consisted of an activated terminal alkyne group that was expected to give rise to Huisgen azide‐alkyne 1,3‐dipolar cycloaddition within the specific pot life for a PU formulation to prevent the migration of plasticizers, and with a gem‐dinitro group as an energy resource. A quantitative miscibility investigation between the plasticizers and uncured GAP showed that REPs exhibited better miscibility than conventional energetic plasticizers. The plasticization effect of the REPs on the GAP prepolymer with respect to the reduction of the viscosity illustrated REPs can effectively reduce the viscosity of the GAP prepolymer from 6,015 cP to 150–240 cP at the processing temperature when 50 wt‐% of REP was added. A comparison of the click reactivity and activation energies (E_a) of REPs and GAP prepolymer elucidated that the reactivity of azide‐alkyne cycloaddition depended on the dipolarophilicity of REPs which could be controlled by adjusting the length of methylene spacer between electron‐withdrawing groups (EWG) and neighboring alkynes in REPs. Thermogravimetric analysis manifested REP/GAP‐based PU binders maintained the thermal stability of the control GAP‐based PU binder. The mechanical properties and impact insensitivity of the GAP‐based PU binders were also improved by the incorporation of REPs.     

城市污泥作为型焦粘结剂的工艺及机理研究

以城市污泥为粘结剂的基础组分,采用化学方法活化,考察了活化剂种类和活化条件对型焦性能的影响,并对型焦的固结机理和结构进行分析.结果表明:磷酸对污泥的活化效果最好,当磷酸浓度为30％、浸渍比为5.3g/mL、浸渍时间为24 h时,生块和熟块的抗压强度均大于5000 N、落下强度分别为7次和8次,耐水性能(浸水24 h干燥后的抗压强度)分别为2575 N和3015 N.生块的热解分为三个阶段,其中磷酸盐分子间发生脱水缩聚最终生成-P-O-M-O-P-高分子结构是粘结兰炭末成型的主要原因.型焦熟块与兰炭末红外吸收峰的位置基本相同,但强度有明显减弱,未出现与磷有关的振动吸收峰,说明磷在型焦中残留量很少.     

Reconstruction and hydration of hydrotalcite response to thermal activation temperature: Enhancement of properties for magnesia castables

Optimization binding system for refractory castables is significant to enhance the service performance. Hydrotalcite has been considered a promoter for high-temperature performance of basic castables, however, its binding property remains to be improved before practical application. In this work, the thermal activated Mg–Al hydrotalcites were incorporated in magnesia castables, and the mutual influence of pre-calcination temperature on the hydration, microstructure, and strength of castables was investigated. The obtained results indicated that the reconstruction of calcined hydrotalcite took place in the hydration process and effectively motivated the hydrolysis. Hydrate was thus promoted and a relatively dense microstructure of magnesia castables was confirmed by X-ray computed tomography analysis. Hydrotalcite pre-calcinated at 300 °C contributed to the highest early strength for castable, and the high-temperature properties also performed better than that of other pre-calcinated hydrotalcite-adding. The enhancement mechanisms of calcined hydrotalcite were attributed to the two following reasons: (ⅰ) the modified microstructure of magnesia castables from the early stage by hydration process, (ⅱ) the further enhanced sinterability inspired by the appropriate thermal activation effect.     

Molasses and air blown coal tar pitch binders for the production of metallurgical quality formed coke from anthracite fines or coke breeze

The effect of the type and the amount of hardeners, such as ammonium nitrate, ammonium carbonate and nitric acid on the molasses bonded briquettes prepared from anthracite fines or coke breeze were investigated. Amongst the hardener studied the best results were obtained with 2.5% ammonium nitrate hardener. The briquettes produced with this hardener were highly water resistant but not waterproof and their tensile strengths were not adequate to be used as a substitute for the metallurgical coke. Therefore, the briquettes were prepared with molasses containing 2.5% ammonium nitrate hardener and air blown coal tar pitch blended binder. When the blended binder was used for the production of anthracite fines or coke breeze briquettes, after curing at 200 °C for 2 h, they became waterproof and their tensile strengths were found to be sufficient to be used as a substitute for coke oven coke. The briquettes after curing could be directly charged into the blast furnace without carbonizing them at high carbonization temperatures. Since molasses and coal tar pitch, are relatively cheap and readily available materials, the process investigated could be economical way of producing high quality formed coke.     

核壳乳液聚合中甲基丙烯酸用量对印花制品的影响

采用核壳乳液聚合法合成涂料印花粘合剂，考察了甲基丙烯酸(MAC)用量的改变对印花产品的牢度和色光的影响：在核中，当MAC的用量分别为0．0g，0．2g，0．4g，0．6g时，干摩牢度分别为25，2．5 ，3,0，3．5，色光由暗变亮；在壳中当MAC的用量分别为0．0g，0.2g，0．4g，0．6g时，干摩牢度分别为2.5，2．5 ，3．0，3．5，色光变亮，对得色量和鲜艳度影响不大。     

开发中国工业型煤之浅见

评述了中国工业型煤的开发和应用现状，并指出型煤质量是影响型煤市场的关键；探讨了冷压成型工艺只是使煤颗粒以物理形式的表面粘合，而热压成型工艺却是赋予煤颗粒以分子结构变化的化学形式的内在焦结，能起到质的变化；提出了热压成型工艺或“冷压成型加高温碳化”工艺，将在助于提高型煤质量和开拓型煤市场。     

无溶剂环氧涂层体积收缩率的研究

涂料在聚合过程中会产生体积收缩,而体积收缩将导致涂层的附着强度大大降低,还可能加速涂层老化的进程。本研究采用三维数字显微镜测试、扫描电镜测试和电化学交流阻抗谱测试等检测方法,对不同体积收缩率的无溶剂环氧涂层进行了性能分析,明确了体积收缩率对无溶剂环氧涂层的微观结构及防腐性能的影响。研究结果表明,调整颜基比可以控制无溶剂环氧涂层体积收缩率的大小;具有较小体积收缩率的涂层其抗渗透能力较好,具有较好的涂层防腐性能。     

机制盘香粘合剂研发

为配合专用盘香加工机的普及使用,研发了机制盘香粘合剂.对盘香加工设备进行了简要说明,对影响盘香性能的主要因素包括粘合剂配方、木粉和粘合剂比例、干粉和水的比例等进行了分析,得到了理想的配比和工艺参数.该粘合剂已经实现工业化生产.     

PET黏合剂及其弹性体热解与推进剂热解相关性研究

采用差示扫描量热/热重(DSC/TG)和裂解气相色谱质谱联用(Py-GC/MS)分析技术研究了PET黏合剂体系、PET/TDI弹性体以及含PET黏合剂体系的简单组分推进剂的热分解特性和热裂解产物状况,探索了PET弹性体的热分解与含PET黏合剂体系的推进剂热解性能之间的相关性.研究结果表明,混合硝酸酯增塑的PET黏合剂体...     

B-GAP对复合固体推进剂能量性能影响理论研究

提高复合固体推进剂的能量性能的方法之一,是将普通的HTPB黏合剂替换成为含能黏合剂B-GAP.利用最小自由能法,对含能黏合剂B-GAP对复合固体推进剂的能量性能影响进行了理论研究,并计算出应用B-GAP的推进剂的燃烧室平衡温度、喷管出口温度、比冲等能量性能参数,将这些性能参数与丁羟推进剂进行比较,发现均有一定程度的提高...