不同制备方法所得PEN纤维的结构性能比较

利用高速纺丝法与纺丝拉伸一步法两种不同的方法制备聚萘二甲酸乙二酯 ( PEN)纤维 ,以DSC、X射线衍射、声速、力学测试等手段分析其结构、热学及力学性能并进行比较。结果表明 :以上两种纺丝法所制备 PEN纤维的晶型、晶粒尺寸不同 ;在所采用的高速纺丝速度范围内 ,分别以 6,7,8km/m in的速度纺制的试样结构性能基本相同 ;而纺丝拉伸一步法中不同的拉伸倍数对纤维的取向度影响较大 ,进而使杨氏模量、断裂强度和断裂伸长率变化较大     

同向双螺杆熔体输送段捏合盘错列角对不相容体系共混物相态结构的影响

对啮合同向双螺杆挤出机,将捏合盘置于熔体输送段,通过改变捏合盘错列角,研究双螺杆挤出过程熔体输送段捏合盘错列角对不相容体系共混物相态结构的影响。应用差示扫描量热仪对两相共混体系HDPE/PS的热性能进行了实验研究,结果表明:螺杆构型对共混物的相容性影响不大。同时采用扫描电子显微镜考察了HDPE/PS共混物在熔体输送段末端位置和机头末端所取试样的相态结构,研究表明:置于熔体输送段捏合盘元件错列角对共混物分散相的相畴尺寸有一定影响。     

无油螺杆压缩机在燃料电池中的应用

由于环境污染、全球变暖、能源短缺等各方面原因,能量转换效率高且无污染的燃料电池汽车备受人们的青睐,作为燃料电池系统中重要部件之一的空气压缩机也成为研究的热点。西安交通大学压缩机研究所成功研制了可以应用于燃料电池的LG300型喷水螺杆空气压缩机以及具有体积小、质量轻、效率高的高速干式螺杆压缩机、膨胀机,并且经过与燃料电池系统配套使用,获得成功。     

PE-UHMW挤出中空吹塑设备与工艺的研究

改型设计了改性超高相对分子质量聚乙烯的挤出中空吹塑设备，设计采用了专用的挤出螺杆、机筒、模头和模具，并研究改进了吹塑工艺及生产方法，从而克服了超高相对分子质量聚乙烯的加工难点，得到了合格的吹塑制品。     

基于STeC的高速列车运行模型与算法

为了使高速列车正点运行到达目的车站,提出了基于STeC(时空一致性)语言的高速列车运行模型与算法。该模型具有位置触发自动调整高速列车运行的特点,实现动态确定高速列车制动点并保证列车正点到达目的车站,从而满足了高速列车运行实时系统对时间和空间的一致性要求。通过Matlab/Simulink的仿真测试,证明了该模型的正确性和有效性。     

实验室RIM机的开发

介绍本所试制的一台实验室用反应注射成型机（RIM0）的主要结构、性能。     

稀磷酸澄清槽泥浆泵改用单螺杆泵的实践

磷酸生产中输送稀磷酸澄清槽淤渣的泥浆泵，各厂的运行情况都不够理想。介绍了三种类型泥浆泵的运行情况，针对淤渣中会出现块结垢物影响泥浆泵长期运行，在单螺杆泵进料腔内设置破碎送料器后，取得了较理想的效果，从而提高了磷酸装置的运转率和磷得率。     

双螺杆转速差决定的螺杆间隙之探讨

根据相对运动原理计算了同向旋转双螺杆因螺杆转速差决定的两螺杆之间的径向和轴向间隙,可为工程上设计这些间隙时提供参考。     

Melting aspects of filled compounds in a modular co‐rotating twin screw extruder

In the polymer industry, precompounded materials are widely used. Carefully designed melting experiments were carried out to investigate melting mechanisms in master batched polymer compounds, using an intermeshing co‐rotating twin screw extruder. Calcium carbonate or aluminum powder was master batched with linear low‐density polyethylene (LLDPE). The calcium carbonates, which were used in the compounds, have differences in weight fraction and particle size. The compounds containing filler have higher thermal conductivities and viscosities than neat polyethylene. We observed melting initiation and propagation mechanisms of LLDPE compounds by removal and characterization of polymer compound carcasses in the melting region. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1990–2012, 2006     

Dynamic reaction inside co‐rotating twin screw extruder. I. Truck tire model material/polypropylene blends

Waste ground rubber tire (WGRT) is a complex composite containing various elastomers, carbon black, zinc oxide, stearic acid, processing oils, and other curatives. Most of the waste ground rubber tire is composed of mainly natural rubber (NR) and styrene butadiene rubber (SBR) in varying proportions. Blending it with other thermoplastic materials is difficult due to the inherent thermodynamic incompatibility. But, the compatibility can be increased by making the reactive sites in WGRT with suitable chemicals under optimum condition of shearing inside a twin screw extruder and it is said to undergo a dynamic reaction inside the extruder. To understand the mechanism of dynamic reaction process of a rubber/polyolefin blend, the blending of a truck tire model material rubber with polyolefin was first tried before it was applied to waste WGRT material. It was observed that the blends of a truck tire model rubber material and PP thermoplastic are physical mixture of two incompatible polymers in which a continuous plastic phase is largely responsible for the tensile properties. The rubber particles are the dispersed phase. The large particle size and the poor adhesion of these rubber particles are believed to be liable for the poor tensile properties. In case of blends of truck tire model material with isotactic polypropylene the tensile properties are found to be lower than that of its PP‐g‐MA counterpart which can be attributed to the reaction of the MA with the carbon black particles. A schematic representation of the possible interactions has been proposed. The effect of addition of compatibilizers such as SEBS and SEBS‐g‐MA has also been studied. The tensile and TGA studies indicate that the polarity of SEBS and SEBS‐g‐MA induces an increase in the performance characteristics for both types of polyolefins but the intensity of this increase is higher in the PP‐g‐MA based blends. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 106: 3193–3208, 2007