纳米碳酸钙在PVC汽车底涂体系触变性的研究

通过实验表明:在纳米碳酸钙在PVC汽车底涂体系中,随着表面处理剂用量的增加,触变环面积、屈服值、宾汉黏度都减少;表面处理剂的C链增长而触变环面积、屈服值、宾汉黏度增大;影响触变性的最大因素是纳米PCC的比表面积大小,比表面积的增大,纳米PCC的粒径减小,而触变环面积、屈服值、宾汉黏度均增大。通过控制得到与苏威SPT性能一样的产品。     

纳米Al/HTPB悬浮液的流变性能

为改善含纳米铝粉HTPB复合推进剂和PBX炸药的工艺性能,研究了纳米Al与HTPB悬浮液的流变性能,用RS-300流变仪研究了混合时间、混合比例、纳米Al粒度、表面活性剂等因素对悬浮液流变性能的影响.结果表明,在50℃恒温50h,HTPB的表观黏度值变化小,其表观黏度值变化不影响悬浮液的流变性能.随着纳米Al与HTPB质量比的增大和纳米铝粉粒度的减小,悬浮液的黏度系数减小,剪切速率指数增大,假塑性逐渐增强,悬浮液的流变性能变差.表面活性剂能显著降低纳米Al/HTPB悬浮液的初始混合表观黏度和屈服值.     

Al和AP粒径对CL-20推进剂燃面团聚及凝相产物特性的影响

为了研究Al和AP粒径对CL-20推进剂燃面团聚及凝相产物特性的影响,通过铝颗粒团聚可视化拍摄结合凝相燃烧产物(CCPs)特性分析的方法,对CL-20高能推进剂中铝的团聚过程进行了拍摄,并收集了CCPs;统计了燃面处不同粒径团聚物的滞留时间,对CCPs进行了微观形貌观察、物相分析及粒度分布测量,分析了Al和AP粒径对CL-20推进剂团聚及CCPs特性的影响。结果表明,随着团聚物粒径的增大,燃面处团聚物的滞留时间逐渐增大;对于粒径分布在60～270μm之间的团聚物,其滞留时间在1～20ms; CCPs中主要存在Al_2O_3和Al两种物质,包括粒径约1μm的氧化铝烟尘颗粒和粒径大于100μm的团聚物颗粒;Al粒径的减小导致CCPs最大峰值粒度增大,1μm左右的粒子体积分数增大,团聚程度增大;AP粒径的减小导致CCPs最大峰值粒度减小,1μm左右的粒子体积分数减小,团聚程度减小。     

纳米CL-20炸药含能墨水的直写规律

针对MEMS引信中微传爆序列,基于直写技术,研究了由纳米CL-20炸药、黏结剂体系(包括黏结剂和溶剂)和其他添加剂组成的CL-20炸药墨水的直写特性,并制备了3种含能墨水。分析了直写压力、针头直径、直写高度和墨水黏度等因素对直写过程的影响规律。结果表明,随墨水黏度增大,直写线宽减小且减小幅度增大,但黏度过度偏大时,会影响直写线宽的均匀性,配方I在喷头高度为0.50mm和0.75mm时,以及配方III在喷头高度为0.75mm时,均出现了线宽不均的现象;配方II直写线宽稳定更适合直写装药。随着喷管压力的增大,CL-20油墨的打印线宽明显增加,且对于不同针头直径和不同配方墨水压力大小变化相同,线宽的增幅基本相同,当压力由100kPa增加到200kPa,线宽增大约2.5倍。随着喷头内径的增大,油墨的直写线宽明显增大,且线宽增加的幅度越来越大。随着喷头高度的增大,油墨的直写线宽减小。对于直写线宽大于1 285μm的墨水线条,固化后墨水表面均出现气泡,直写时应控制线宽,防止在直写过程中空气进入墨水。     

CL-20含量及其粒度级配对NEPE推进剂燃烧性能的影响

采用静态与水下声发射法测试了CL-20含量及其粒度级配对NEPE推进剂燃速与压强指数的影响;采用DSC与TG-IR联用研究了CL-20对NEPE推进剂热分解行为的影响。结果表明,随着CL-20质量分数由42%增至50%,推进剂燃速与压强指数上升,燃烧效率提高,表明CL-20氧化能力高于GAP/硝酸酯含能黏合剂体系;随着CL-20/HMX、CL-20/Al质量比增高,推进剂燃速上升,燃烧效率上升;CL-20对推进剂燃速和压强指数的贡献高于HMX;随着CL-20/AP质量比增高,CL-20/AP混合体系分解产物氧化能力降低,燃烧反应速率降低,燃速降低;CL-20粒度级配对NEPE推进剂燃烧行为影响显著,当CL-20的粒径(d50)在5~50μm时,随着细粒度CL-20含量增高,推进剂燃速与燃速压强指数下降;当体系中存在超细粒度CL-20(d50=500nm)时,推进剂燃速与燃速压强指数随着超细粒度CL-20含量的增加而有所增加,4种粒度CL-20对NEPE推进剂燃速的贡献顺序为:粗粒度>中粒度>超细粒度>细粒度。     

ZnO在Al_2O_3/导热环氧树脂灌封胶中的应用研究

采用硅烷偶联剂KH-560对ZnO粉体表面改性,研究了ZnO粒径及用量对Al2O3/导热环氧树脂灌封胶导热系数、粘度、拉伸剪切强度、沉降率、触变指数、耐热性的影响。结果表明:表面改性后的ZnO粉体颗粒分散均匀,无明显团聚现象;相同用量时,填充0.5μm ZnO的树脂体系的综合性能较5μm ZnO体系好。随ZnO用量的增加,灌封胶的导热系数、拉伸剪切强度、触变指数均呈先增大后减小的趋势,ZnO添加质量分数为20%时灌封胶导热系数、拉伸剪切强度最大,分别为0.84 W/(m·K)、16.78 MPa,ZnO添加质量分数为60%时触变指数最大为1.89。随ZnO用量的增加灌封胶的粘度、耐热性均逐渐增大,沉降率逐渐降低。     

含CL-20的NEPE固体推进剂的性能

用高能氧化剂六硝基六氮杂异伍兹烷(CL-20)部分代替NEPE推进剂基础配方中的RDX,研究了CL-20含量、粒度大小对NEPE推进剂能量性能、燃烧性能、力学性能的影响规律。结果表明,在低铝含量NEPE推进剂中加入CL-20后,比冲可提高约54N.s/kg;加入CL-20后,NEPE推进剂在各压力点下的燃速明显比含RDX的NEPE推进剂燃速高,但压力指数差别不大;随着CL-20粒度的增加,燃速呈现先增后降的趋势,在105~125μm时达到最大值,燃速压力指数则表现为先降后增的趋势,105~125μm时最低,最低值为0.423;随CL-20粒径的变化,NEPE推进剂的力学性能有大幅度的变化,粒径为125~154μm时,其综合力学性能最佳。     

高浓度超高相对分子质量聚乙烯冻胶流变行为的研究

应用Rosand RH7D型双料筒毛细管流变仪,研究了以白油为溶剂的高浓度超高相对分子质量聚乙烯(UHMWPE)冻胶的流变特性,以及冻胶浓度、温度对高浓度冻胶的流变曲线、非牛顿指数和结构黏度指数的影响。结果表明:高浓度UHMWPE冻胶属于宾汉流体,不同浓度的UHMWPE冻胶非牛顿指数随温度的升高先增大后减小,结构黏度指数随UHMWPE冻胶浓度及温度的增高而减小。     

PP/稀土铝酸锶复合材料流变性能研究

采用毛细管流变仪对聚丙烯(PP)/稀土铝酸锶复合材料的流变性能进行了研究,主要分析了温度、稀土铝酸锶含量对PP/稀土铝酸锶样品的表观黏度、非牛顿指数、黏流活化能和结构黏度指数的影响。结果表明,随着稀土铝酸锶添加量的增加、温度的升高,PP/稀土铝酸锶熔体表观黏度逐渐降低;在相同温度下,随着稀土铝酸锶含量的增加非牛顿指数n出现先增大后减小,在稀土含量一定的条件下,随着温度的升高,非牛顿指数逐渐增大;随着稀土铝酸锶含量的增大,黏流活化能先减小后增大;随着温度的提高,结构黏度指数逐渐降低,而随着稀土铝酸锶含量的增加,结构黏度指数呈先降低后增加的趋势。     

骨料粒度级配对Al_2O_3-SiC自流浇注料流动性和流变特性的影响

为了进一步研究骨料的粒度级配对Al_2O_3-SiC自流浇注料流动性能和流变特性的影响,通过正交试验法研究了5~3、3~1和≤1 mm的棕刚玉骨料的粒度级配对浇注料的自流值、相对塑性黏度和相对屈服应力的影响。结果表明:1)试验浇注料的自流值和相对塑性黏度均随3种不同粒度棕刚玉骨料加入量的增加而减小,而棕刚玉骨料粒度对浇注料自流值和相对塑性黏度的影响程度则均随其粒度的减小而增大;2)试验浇注料的相对屈服应力随5~3 mm棕刚玉骨料加入量的增加略有减小,随着≤1 mm棕刚玉骨料加入量的增加略有增大,随着3~1 mm棕刚玉骨料加入量的增加变化不大,并且无规律;3)≤1 mm棕刚玉骨料对浇注料相对屈服应力的影响最大,其次为5~3 mm的,3~1 mm的影响最小。     

Rheological behavior of multi-sized SiC inks containing polyelectrolyte complexes specifically for direct ink writing

In order to simultaneously improve both the solid loading and rheological behavior of ceramic ink during direct ink writing (DIW) process, the polyelectrolyte complexes have been used as rheological modifiers. Based on the Funk-Dinger function, the maximum solid loading of multi-sized SiC ink reached 63 vol%. The viscoelasticity of SiC inks with different [COOH]:[NH_x] molar ratios was investigated and the mechanism of polyionic chains on rheology was analyzed. When the [COOH]:[NH_x] molar ratio was 1:0.1, the SiC ink exhibited excellent thixotropic behavior and formability. The effect of particle size on rheological behavior of SiC ink was investigated to clarify the correlation between polyelectrolyte complexes and multi-sized SiC.     

Synthesis and characterization of hetarylazo disperse colorants: Preparation and properties of conventional and microemulsified inks for polyester ink‐jet printing

The synthesis and characterization of three hetarylazo disperse colorants are described. These compounds were used for the preparation of conventional inks and/or oil‐in‐water microemulsions (microemulsified dyes). The viscosity, conductivity, surface tension, and pH of these inks were studied over a period of time and discussed with respect to their structure. The particle size and particle size distribution of a representative microemulsion were compared to those of a corresponding conventional ink. The measured properties were compared to the properties of commercially available inks. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

LLM-105/CL-20基高能钝感PBX的制备与性能表征

为满足含能材料高能钝感的要求,以CL-20为主体炸药,LLM-105为钝感剂,采用溶液水悬浮法制备了LLM-105质量分数分别为10%、20%、30%的3种LLM-105/CL-20基PBX。通过扫描电子显微镜(SEM)、粉末X射线衍射仪(PXRD)和差示扫描量热仪(DSC)对样品的形貌、晶体结构和热性能进行表征,并测试其机械感度;采用EXPLO5软件计算了其爆轰参数。结果表明,LLM-105/CL-20基PBX样品呈类球形,颗粒密实,粒径约为500μm;PBX中各组分的晶体结构未发生改变;3种配方的热安定性都较好,且随着钝感剂LLM-105含量的增加,LLM-105/CL-20基PBX的热爆炸临界温度呈递增趋势;与原料CL-20相比,3种LLM-105/CL-20基PBX的特性落高分别提高了25.88、33.68、37.18 cm,摩擦爆炸概率分别下降29%、38%、45%;LLM-105质量分数为10%的LLM-105/CL-20基PBX的特性落高与PBX-9501相当,而LLM-105质量分数为20%和30%的LLM-105/CL-20基PBX分别比PBX-9501高16.6%和25.12%;理论爆速分别高381.76、279.2、82.03 m/s。3种配方LLM-105/CL-20基PBX炸药的爆轰性能明显优于PBX-9501。     

Synthesis,characterization, and application of hetarylazo disperse colorants: Preparation and properties of ink-jet inks with active agents for polyester printing

The synthesis and characterization of two hetarylazo disperse colorants are described. These compounds were used for the preparation of ink-jet inks with and without active agents for polyester printing. The viscosity, conductivity, surface tension, and pH of these inks were studied over a period of time and discussed with respect to their structure and the active agent content. The particle size and particle size distribution of a representative ink containing a new synthesized hetarylazo compound were measured. All the prepared inks were proved to be suitable for ink-jet printing in terms of their particle size. Viscosity , surface tension, conductivity, and pH values of all inks, with and without active agent, were monitored over a period of 90 days and were related to the ink stability. The same properties were measured for an ink preparation with a commercial dye for comparison. The inks containing the new synthesized dyes were found to be more advantageous regarding most of the above properties, i.e., surface tension, viscosity, and conductivity. Contrarily pH values of all the preparations were unacceptable for ink-jet inks. The ink compositions containing the new synthesized compounds were applied by exhaustion (dyed) on polyester fabric. Fastness properties of the dyed polyester samples were excellent to very good in most cases. Color measurements of the dyed fabric were also performed. A qualitative determination of the aroma-active agent adsorbed on the fiber by the exhaustion method was achieved by the GC-MS method. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

铝粉含量和粒径对乳化炸药作功能力的影响

为研究铝粉对乳化炸药作功能力的影响,在负氧平衡的乳化炸药中分别添加不同含量和粒径的铝粉,采用测时仪法测定其爆速;通过水下爆炸实验计算出含铝乳化炸药的比冲击波能、比气泡能和总能量等参数。结果表明,当铝粉(粒径为5μm和35μm)质量分数为5%时,含铝乳化炸药的爆速最大,分别为5 128、5 071m/s;当铝粉(粒径为5μm和35μm)质量分数为20%时,乳化炸药的比冲击波能、比气泡能、总能量均随着铅粉含量的增加而增大,比冲击波能分别增加19.7%、15.3%;比气泡能分别增加12.6%、13.7%,总能量分别增加15.1%、14.5%。     

DNP/HMX熔铸炸药的流变性能

为了解3,4-二硝基吡唑(DNP)/HMX悬浮液在不同影响因素下的流变行为,采用Brookfield R/S Plus流变仪对其流变性能进行测试,分析了HMX含量、粒度、颗粒级配、体系温度以及不同添加剂对悬浮液流变性能的影响。结果表明,DNP单质为牛顿流体,表观黏度约为16.4mPa·s,比TNT高82%,比DNAN高140%;同一剪切速率下,DNP/HMX悬浮液表观黏度随固含量的增加而增加,当HMX质量分数为30%时,悬浮液近似牛顿流体;HMX质量分数高于30%时,表观黏度随剪切速率的增加呈指数型下降的趋势愈发明显;悬浮液表观黏度随颗粒粒径的增大和温度的增加而降低,当温度从95℃升到105℃时,黏流活化能(E)从29211J/mol增至38458J/mol;固含量为60%时,平均粒径(d50)分别为16.6μm和575.6μm的HMX颗粒的最佳质量比为1∶5,此时悬浮液表观黏度最小。N-甲基-4-硝基苯胺(MNA)降低了悬浮液的表观黏度,乙酸丁酸纤维素(CAB)和微晶蜡-80(MV80)增加了悬浮液的表观黏度。     

Optimization of the ceramic ink used in Direct Ink Writing through rheological properties characterization of zirconia-based ceramic materials

Understanding and optimization the rheological properties characterization of zirconia (ZrO₂) based ceramics inks is critical for optimizing the production of Direct Ink Writing (DIW) components to achieve complex structures with similar properties as those obtained by using the traditional processing routes. In this work, ZrO₂ based ceramic materials with different yttrium contents (3 and 8 mol %) were designed and produced by DIW to determine the most suitable ceramic ink composition in terms of the rheological properties (e.g. flow curves, viscosity, loss modulus G′, storage modulus G″, etc.) to design new components. Different ceramic inks with charges up to 75 wt % were prepared and characterized. A systematic study of the feedstock, as well as the different ceramic inks, was performed to determine the optimal ceramic charge. This characterization evidences that rheological properties of zirconia based ceramic inks are influenced by the particle size and amount of ceramic content. Furthermore, the rheological study highlights that the ZrO₂ inks present a Non-Newtonian behavior depending on the ceramic content. Results revealed that the yttrium content affects the flow properties of ZrO₂ suspensions in such a way that, higher shear rate was required to make the suspensions flow at increasing the amount of powder. It was also found that the best rheological properties corresponded to 73 and 70% for the 3Y- and 8Y–ZrO₂ of ceramic charge, respectively.     

丙烯酸酯单体结构对UV油墨的流变性和分散性的影响

油墨的印刷适性与其流变学性能和分散性密切相关,UV单体是影响油墨的流变学性能和分散性的主要因素。本论文使用不同UV单体研制了UV丝印油墨,重点探讨了TMPTA、EO3-TMPTA、PO3-TMPTA三种单体的结构对研制的UV丝印油墨的粘度、触变性、动态粘弹性和油墨细度的影响。     

一锅法制备CL–20混合炸药的工艺研究

以CL–20为主体炸药,聚氨酯5702为黏结剂,Span60为表面活性剂,通过一锅造粒法制备了CL–20混合炸药。用单因素实验对影响CL–20混合炸药包覆效果和撞击感度的因素进行了研究,对包覆后的CL–20混合炸药的相关性能进行了测试,得到最佳工艺条件:水浴温度65℃,搅拌器电压为90 V,驱溶时间为1 h,2次加入溶剂的量与高聚物的质量比为4:1。