Model to Study Resin Impregnation Process of Premix Made of Friction Spun Core Yarn

A model was developed to investigate impregnation behavior of thermoplastic resin into filament bundle based on Darcy's law. Consolidation processes of unidirectional laminate were performed to evaluate the validity of the model. Friction spun core yarns were used in the experiments with polypropylene fiber sheath and glass filament core. The processing conditions, such as temperature and pressure, and filament parameters were taken into consideration. A good agreement was found between theoretical prediction and experiment data.     

摩擦纺包缠纱抗剥离性能的测试

推荐一种包缠纺抗剥离性能的测试方法。在电子万能试验机上,利用专用的测试装置可连续地测试覆盖纤维相对于芯纱剥离时的阻力;同时分析了影响测试结果的因素,并将结果与同种纱线在Y73l型抱合力仪上的耐磨次数进行比较,并在织造实践中予以验证。     

Testing of Anti - stripping Property of Friction Spun Core Yarn

Friction spun core yarn has two components: filament core and staple fiber sheath. Under axial rubbing action, the failure mode of the core yarn is the stripping of the sheath from the core. This paper introduces a method to test the anti - stripping property of the core yarn. With a modified Universal Testing Machine, the stripping resistance of friction spun core yarn can be continuously measured. Some factors Influencing the measurements are discussed in detail. The testing results are compared with those from a Y731 Yarn Abrasion Tester and fur - ther confirmed by weaving practice.     

环氧大豆油扩链内增韧酚醛树脂的合成与应用

合成了一种具有优异韧性和热稳定性的覆铜板用环氧大豆油内增韧改性酚醛树脂.采用FTIR表征了改性酚醛树脂的分子结构,用SEM观察了改性酚醛树脂样品冲击断面的微观形貌,并对改性酚醛树脂制备的覆铜板的性能进行了研究,以获得最佳的合成工艺.文中还对改性酚醛树脂的增韧机理进行了探讨,发现其主要反应机理为:部分环氧大豆油在叔胺催化下与酚羟基进行醚化反应,同时环氧大豆油与多元胺发生扩链反应,最终生成与酚醛预聚体接枝的长链环氧大豆油环氧树脂.当环氧大豆油添加量为30%、固化剂含量达7%时,树脂的综合性能较佳.扩链后的环氧大豆油具有显著的增韧作用,它与酚醛树脂构成内增韧的交联网络,内增韧结构对改善覆铜板的耐焊性起着关键作用.     

修复-润滑双功能微胶囊/环氧树脂复合材料的摩擦学性能研究

以润滑剂（亚麻籽油、聚α烯烃或1-丁基-3-甲基咪唑六氟磷酸盐）和修复剂（邻苯二甲酸二丁酯）为芯材,脲醛树脂为壳材,采用原位聚合法合成了双芯材微胶囊,将微胶囊填充在环氧树脂中得到固体自润滑复合材料;使用扫描电子显微镜（SEM）、傅里叶变换红外光谱仪（FT-IR）、热重分析仪（TGA）对微胶囊进行了表征;使用摩擦磨损试验机、三维白光干涉仪、光学显微镜、扫描电子显微镜测试了微胶囊/环氧树脂复合材料的摩擦和修复性能。结果表明,微胶囊在整体上呈球形,结构完整,两种芯材均成功包覆;当加入质量分数为10%的微胶囊（芯材为亚麻籽油和邻苯二甲酸二丁酯）时,与环氧树脂相比,在摩擦试验测试1 200 s后自润滑复合材料的摩擦系数降低了约90%,在磨损试验测试2 h后其磨损体积减小约3个数量级（由10¹⁰ μm³减小到10⁷ μm³）;被划伤的复合材料经50℃加热1 h后,与加热前相比划痕变窄、变浅。以上结果表明,制备的双功能微胶囊/环氧树脂复合材料的耐摩擦磨损性能相对环氧树脂有所提高,同时具有良好的自修复特性,极大地提高了复合材料的综合使用性能。     

热解终温对酚醛树脂层压板真空热裂解产物的影响

采用程序升温的热解反应器对酚醛树脂层压板的真空热解规律进行研究,着重考查不同热解终温对热解产物产率和热解油组成的影响,同时利用元素分析、工业分析、热重分析、GC-MS分析对层压板原料及产物油进行分析。研究结果表明:酚醛树脂层压板裂解可获得产率分别为50.25%～54.58%,33.00%～41.00%和8.75%～12.95%的液体、固体和气体,其产物油的成分主要为酚类、磷酸芳基酯类、脂肪酸酯类、腈类等物质;随着热解终温的升高,固体产率逐渐下降,液体产率在650℃有1个峰值,而气体产率则呈上升趋势,并且双酚F、双酚A、长链脂肪酸酯、磷酸三芳基酯等相对分子质量较大的物质含量逐渐降低,而苯酚、甲酚、二甲酚、对异丙基苯酚等相对分子质量较小的物质含量逐渐增大;样品有3个主要的质量损失台阶(在190～320,320～390和390～510℃),热质量损失率分别为9%,20%和31%。     

芯丝预加张力对摩擦包芯纱强力的影响

纺制摩擦包芯纱是提高摩擦纱强力的一个有效手段。该文对摩擦包芯纱的加捻过程进行了动力学分析,获得了加捻过程中纱线转动速度n(x)和捻度T(x)的变化规律。以棉纤维为外包纤维,对涤纶、锦纶6及粘胶长丝等三种不同材料的芯丝对芯丝预加张力对摩擦包芯纱强力影响的问题进行了试验研究。利用理论研究的结果对试验规律进行了分析和解释。     

包缠结构预混料热压过程中树脂浸渍分析

建立了包缠结构顸混料热压过程中树脂的浸渍模型。结果表明,实验值和模型的预测值吻合较好,该模型可以用于包缠结构预混料热压过程中浸渍时间的预测。利用该模型对混合结构预混料的进一步研究发现,包缠结构预混料中丝束的完全浸溃时间仅略长于混合结构预混料。     

摩擦－喷气复合纺成纱结构的研究

从理论和实际上论述了摩擦－喷气复合纺纱的加捻过程，并利用电子显微镜和示踪纤维方法对摩擦－喷气复合纱和色芯摩擦纺分别进行了分析和测量，发现摩擦－喷气复合纱的芯纱比包芯摩擦纱的芯纱具有较多的包缠纤维和较高的包缠捻度，表明摩擦－喷气复合纺纱有利于提高成纱强力．     

纺速对PEIT卷绕丝超分子结构及力学性能的影响

借助由X射线衍射法，密度法，DSC法测定的结晶度和沸水收缩率，自然拉伸比，声速取向因子等指标来描述纺丝速度在2400－5000m/min范围内变化的PEIT卷绕丝的超分子结构。在实验的纺速范围内，PEIT卷绕丝的结晶度随纺速增加的过程中有突变现象，这主要是因为分子取向诱导所致。最后，就不同纺速下PEIT初生丝的力学性能特征值进行了对比。     

圆盘式旋流纺纱的工艺分析

介绍了圆盘式旋流纺纱的装置和流程，探讨了影响圆盘式旋流纺纱成纱性能的主要工艺参数，成功地纺制了包芯纱．为了解和掌握圆盘式旋流纺纱设备的纺纱性能、工艺特点，对所纺纱线的强度和耐磨性进行了测试．根据测试结果，分析了圆盘式旋流纺纱的主要工艺参数与成纱性能之间的关系，发现第一喷嘴压力、第二喷嘴压力、梳辊转速、喂棉量、棉条号数、喂入张力、芯纱退绕张力是圆盘式旋流纺纱的主要工艺参数．     

Liquid crystalline spinning of spider silk

Spider silk has outstanding mechanical properties despite being spun at close to ambient temperatures and pressures using water as the solvent. The spider achieves this feat of benign fibre processing by judiciously controlling the folding and crystallization of the main protein constituents, and by adding auxiliary compounds, to create a composite material of defined hierarchical structure. Because the 'spinning dope' (the material from which silk is spun) is liquid crystalline, spiders can draw it during extrusion into a hardened fibre using minimal forces. This process involves an unusual internal drawdown within the spider's spinneret that is not seen in industrial fibre processing, followed by a conventional external drawdown after the dope has left the spinneret. Successful copying of the spider's internal processing and precise control over protein folding, combined with knowledge of the gene sequences of its spinning dopes, could permit industrial production of silk-based fibres with unique properties under benign conditions.     

端酚基超支化大分子的合成

通过两步法反应合成了新型的AB₂单体4-(6-溴-己氧基)-4′,4″-二羟基三苯甲烷,并进一步在温和的反应条件下得到端基为酚羟基的超支化聚醚型大分子,研究了反应时间、反应温度、单体浓度和核分子的加入对超支化分子的分子量及其分布的影响。除AB₂单体法外,还利用A₂+B₃法合成了结构类似的超支化分子,并对比了两种不同合成方法对超支化分子的分子量及分子量分布的影响。通过A₂+B₃单体合成的超支化分子可作为添加剂来改性E-51环氧树脂,添加质量分数10%的该超支化分子就能极大地提高用酸酐固化的环氧树脂的耐碱性。     

磷酸酯改性呋喃树脂固砂剂的制备及性能研究

针对树脂固砂剂一直存在固砂强度与地层渗透率保留率之间的矛盾,开展了磷酸酯改性呋喃树脂固砂剂的研究,研究中以磷酸、聚醚（L35）、呋喃树脂为主要原料,通过羟基缩聚制备出磷酸酯改性呋喃树脂水性聚合物,并将其用水稀释3倍后作为油田固砂剂使用,一方面,以水作为天然增孔剂,另一方面,在水环境下成膜固化,既保证了固砂强度,又保证了高地层渗透率,有效解决了长期困扰化学防砂效果的难题。研究结果表明,磷酸酯改性呋喃树脂用水稀释3倍浸入砂粒后,于水下环境中60～80℃保温48 h可固结砂粒,固砂强度大于4 MPa,适合油田水下环境固砂。截至2019年3月,现场应用10口油井,控砂成功率达100%,累计增油13 000 t,应用效果良好。     

REPORT ON A PROJECT AIMED AT INCREASING THE STRENGTH OF FRICTION SPUN YARN BY USING A FALSE TWIST PROCESS

The lower strength of friction spun yarns has became a key problem that hinder the develop-ment of friction spinning,especially in high speeds and fine yarns.In this paper a project aimed atincreasing the strength of friction spun yarns by using a false twist process has been made.In re-ported experiment false twist was inserted into the yarn which has been formed on a friction spin-ning machine,so that it made the yarn untwist at first,then regain the twist.In the meantime draftwas applied to generate more tension than that which had been experienced during yarn formationon the friction spinning machine.It made the yarn reforming and the loosely bound fibres in thefriction spun yarn formed due to extremely low tension on the friction spinning machine becametighter.Results indicate that with the proper draft,tension and false twist the tenacity of processedyarn will increase more than 10%.This project is an attempt to discover whether improvements can be made and whether it isworth pursuing research into modifications of yarn structure.The results imply that if the yarntension can be raised during yarn formation on the friction spinning machine or a chance is offeredto the yarn to reform after the yarn formation the yarn tenacity will be increased obviously.     

低档兔毛纺纱工艺路线探索

低档兔毛纤维短,本文采用棉型纺纱系统,可以纺制18 tex以细的纱,这样有利于开发薄型产品。但纯兔毛纱强力较小,可用涤丝包芯方式采加固。产品经济实惠,适合内销市场需要。本文工艺采用短流程,基本上在棉纺设备上加以改装后纺制成纱。     

纳米铜对酚醛树脂及摩擦材料性能的影响

采用原位同生法成功地制备了纳米铜改性酚醛树脂.利用X射线衍射分析和透射电子显微镜对所制备的树脂进行了表征,结果显示酚醛树脂中的纳米铜粒子分散良好,粒径为10～40nm.通过热重分析、冲击试验和摩擦试验,分别研究了纳米铜对酚醛树脂及摩擦材料性能的影响,结果表明:随纳米铜含量的增加,酚醛树脂的初始分解温度和半分解温度先升高后降低,在其质量分数为7%时分别达到最大值;随纳米铜含量的增加,摩擦材料的冲击强度先增大后下降,在其质量分数为5%时达到最大值;纳米铜可改善摩擦材料的摩擦磨损性能,尤其在高温下可使摩擦材料的热衰退明显减轻,磨损率显著下降.     

Friction and Wear Behaviors of C/C-Si C Composites under Water Lubricated Conditions

C/C-SiC composites have the potentiality to be applied in shield pumps of nuclear reactors as the bearing material because of their low density, good mechanical properties and excellent tribological properties. The C/C-SiC composites are fabricated via reactive melt infiltration(RMI) using silicon liquid infiltrated in C/C matrix composites. Friction and wear behaviors of C/C-SiC composites under water lubricated conditions are investigated using the block-on-ring test at room temperature, and compared with those of the resin graphite which is used as the bearing material in shield pumps at present. In addition, friction and wear mechanisms of C/C-SiC composites under water lubricated conditions have been discussed. Results show that tensile strengths of C/C-SiC composites are 150-210 MPa, and compressive strengths are 403-536 MPa. Friction and wear behaviors of C/C-SiC composites are closely related to the load and the speed. The time to reach a stable friction status decreases with the increase of the speed. Though the friction coefficient of C/C-SiC composites under water lubricated conditions is slightly higher than that of graphite, the wear rate of C/C-SiC composites is much lower, which suggests that the C/C-SiC composites can sustain a longer life during operation.     

自凝与热凝树脂义齿材料摩擦磨损行为对比

在自制的往复摩擦磨损实验台上,以球面接触方式,在干摩擦、法向压力为20N、往复频率为0.5Hz、摆幅85mm条件下,研究了牙科用的自凝和热凝树脂球分别对自凝树脂板的摩擦磨损行为.实验过程中利用动态应变仪测量摩擦过程中应变片的应变,进而计算出摩擦系数.结合电镜观察比较得出了自凝与热凝2种义齿材料的耐磨性能:自凝树脂义齿材料磨损过程中会出现材料塑性流动和表面致密的光滑层,磨损轻微,后者材料致密性差有气孔,磨损过程中出现层状磨损,气孔周围材料易脱落,结果自凝材料的摩擦系数低于热凝材料,且耐磨性高于热凝材料.     

环氧树脂乳液泡沫制备及固砂性能研究

为了克服化学防砂中存在的缺陷,改善其应用效果,开展了环氧树脂乳液泡沫固砂性能的研究.以环氧树脂、自制乳化剂为原料,采用相反转法,合成了具有较低黏度的环氧树脂水乳液.将合成的乳液稀释与起泡剂、稳泡剂混合搅拌可得到稳定性良好的泡沫.实验表明,在室温下质量分数50%乳液中,当起泡剂与稳定剂用量分别为乳液质量的0.4%、3.0%时,起泡体积倍数大于4,半衰期可达到29 h以上.通过室内模拟固砂实验发现,采用环氧树脂乳化泡沫固砂,所固结岩心强度高,渗透性好,抗压强度可达5 MPa,可以为非均质油藏或水平井的防砂提供一种有效的手段.