Effect of Dip Coating Process on the Performance of Graphene/Spandex Yarn Strain Sensor

This study presented the effect of the concentration of graphene in the dispersion,the type of polyvinyl alcohol( PVA) and the surfactant on the sensing properties of dip-coated graphene/spandex yarns as resistance strain sensors. Experimental results showed that the addition of styrene-acrylic emulsion surfactant facilitates the dispersion of graphene and then improves the conductivity and sensing performance,and the sensitivity is up to 91. The conductivity and sensing properties of graphene/spandex yarns at 2% graphene dispersion are better than those at 1% graphene dispersion. When the conductive yarn treated by 2% graphene dispersion is stretched to 50%, the sensitivity is up to 29, the repeatability is good,and the hysteresis is low. In terms of the binding agent,PVA as a high alcoholysis and large polymerization decreases the sensitivity,repeatability as well as the hysteresis.     

锦纶66包芯纱牛仔面料开发

使用锦纶66纤维开发高性能、高品质的牛仔面料,以粘胶为外包纤维,锦纶66或氨纶为芯丝制成36.4和28.0 tex的包芯纱为纬纱,使用剑杆织机使其与36.4和28.0 tex的纯棉纱线进行交织,制成牛仔面料。对锦纶66包芯纱和氨纶包芯纱所织制的6种牛仔面料进行色牢度、耐磨性、强力、弹性回复性、折皱回复性和弯曲性能等性能测试并进行对比分析,发现锦纶66包芯纱牛仔面料的弹性达到氨纶包芯纱牛仔面料的弹性水平,且其强力和柔软度更佳。以粘胶/锦纶66(3.33 tex/10 F)包芯纱织制面料比粘胶/锦纶66(3.33 tex/34 F)强力更大、弹性回复性更好,且更柔软。同时,采用36.4 tex纱线所织制的面料的强力、弹性和折皱回复性更好,但28.0 tex纱线所织制的面料更柔软。     

LIPN聚氨酯/聚丙烯酸酯粒子形态结构的研究

采用二步法的技术制备了涂料用基料胶乳互穿网络聚合物聚氨酯 /聚丙烯酸酯( LIPN PU/PA) ,即首先合成种子聚氨酯水分散体 (网络 PU) ,然后合成 LIPN PU/PA。采用电子显微镜观察了 LIPN PU/PA的粒子形态结构以及引发剂种类和网络 PU与网络 PA的相对用量对粒子形态结构的影响。测试结果表明 ,LIPN PU/PA具有两相的“翻转”型核壳结构 ;采用油溶性引发剂偶氮二异丁腈 ( AIBN)可以得到具有“翻转”型核壳结构的粒子 ,但使用水溶性引发剂所得粒子几乎无“翻转”型核壳结构 ,而前两种引发剂的复合体系所得粒子形态则介于两者之间 ;随着网络 PU用量的减少 ,乳胶粒子越来越大 ,但其形态基本上具有“翻转”型核壳结构     

锦纶经编网片断裂强力特性研究

以国家有关测试标准为依据，采用裂区模型实验设计方法对多种系列锦纶复丝经编网片测样进行测定，数据采用多元方差分析方法，分析了网片纵横向之间、干湿态之间的断裂强力和断裂伸长率的差异性，找出了影响网片断裂强力和断裂伸长率的主要因素，分析了各主要因素影响的程度和趋势，回归各因素与断裂强力和断裂伸长率间的关系。研究分析结果表明，锦纶经编网片的断裂强力和断裂伸长率均与目脚总纱数、编织密度和成圈纱数有高度显著的线性关系。     

POE-g-MAH增韧改性PA6的力学性能

研究了接枝马来酸酐的乙烯-辛烯共聚物（POE-g-MAH）对增韧改性尼龙6（PA6）力学性能的影响结果表明：随着POE-g-MAH含量的增加,PA6的拉伸模量和强度及弯曲模量和强度均有所下降,但冲出强度和断裂仲长率均显著提高;增韧改性后PA6断面形貌明显成韧性断裂,且其熔体流动速率随POE-g-MAH含量增加而下降;当POE-g-MAH质量分数为25％时,增韧PA6的综合性能最佳,可用作PA柔性管材专用料。     

聚酰胺纳滤膜在活性染料低盐化加工中的应用

将聚酰胺(PA)质地的纳滤膜组装成一种脱盐装置。在此装置上对C．I．活性蓝49染料进行了低盐化中试实验,结果表明,此装置可以将该染料中的无机盐(以NaCl计)含量从7．4％脱除到0．39％,在此过程中C．I．活性蓝49的回收率达到98％。     

GO/PPy/Pb3O4修饰电极的制备及其在电化学传感中的应用

通过制备氧化石墨烯/聚吡咯/四氧化三铅(GO/PPy/Pb₃O₄)复合材料,用于构建电化学传感器,以实现对对苯二酚的电化学检测。通过利用π-π共轭效应,实现吡咯单体在氧化石墨烯表面的原位聚合。以GO/PPy纳米复合材料为基底,通过水热反应制备得到具有微/纳结构的GO/PPy/Pb₃O₄复合材料。以扫描电镜(SEM),傅里叶红外(FTIR)和X射线衍射(XRD)等对复合材料进行表征,用差分脉冲伏安法研究对苯二酚在修饰电极上的电化学行为。通过对比不同修饰电极的电化学传感性能,发现GO/PPy/Pb₃O₄修饰电极展示了良好的导电性和优异的电催化性能。结果表明,该电化学传感器在1.0~35 μg/L范围内与其氧化峰电流呈良好的线性关系,其检测限为0.3 μg/L。此外,该电化学传感器还具有良好的重现性和稳定性。     

Injectable Premixed Cement of Nanoapatite and Polyamide Composite

A new type of injectable premixed bone cement consisting of nano-hydroxyapatite (n-HA) and polyamide 66(PA66) composite is investigated.This cement can be handled as paste and easily shaped.which can set in air,in physiological saline solution and in blood.The setting time,injectability and compressive strength of the cement largely depend on the ration of liquid to powder (L/P),Moreover,the content of n-HA in composite also affects the compressivce strength and injectability of the cement.The premixed composite cement can remain stable in the package for a long period and harden only after delivery to the defects site.The results suggest that injectable premixed cement has a reasonable setting time,reasonable viscosity for injecting,excellent washout resistance and high mechaical strength,which can be developed for root canal filling,sealing and various bone defects augmentation.     

温度对生物基聚酰胺56氢键的影响

利用傅里叶变换红外光谱仪测定了升降温过程中聚酰胺56(PA56)的系列红外光谱,考察了PA56红外光谱中酰胺Ⅰ带、酰胺Ⅱ带及N—H伸缩振动谱带随温度变化的情况,分析了温度对PA56氢键的影响。研究发现,随着温度的升高,氢键键合羰基与氨基的红外吸收谱带的峰强逐渐减小,而游离羰基、氨基的红外吸收谱带的峰强缓慢增大。由此表明PA56的氢键密度随着温度的升高而降低。     

聚己内酰胺分离纯化缩宫素粗品研究

通过考察在不同乙腈浓度等度洗脱条件下,缩宫素在聚酰胺色谱柱上的保留,研究了聚酰胺对缩宫素的分离机理,建立并优化了聚酰胺对缩宫素粗品的粗分离方法,并与反相C18分离效果进行对比.缩宫素在聚酰胺色谱柱上的保留呈现典型的氢键吸附和疏水作用吸附共同作用的混合吸附模式;在优化的纯水等度洗脱分离缩宫素粗品的条件下,样品栽量可达9.38 mg/mL介质,纯度可达65.8%,回收率72.1%.研究结果表明,聚酰胺纯水等度洗脱分离缩宫素粗品有着与传统反相C18分离基本相当的效果,与反相C18相比还有着样品栽量高、经济、安全和环保等优点.     

Effect of Blending Ratio on Properties of Core Yarn and Fabric of Polysulfonamide(PSA)/Flame Retardant Viscose(FRV)/Conductive Filament

In order to develop a fabric with excellent flame resistance function, antistatic function, moisture absorption and breathability, the polysulfonamide(PSA) fiber and the flame retardant viscose(FRV) fiber were blended. Meanwhile, the conductive filaments were used as the core yarn, and then they were made into the core-spun yarn and the fabric at different blending ratios of PSA/FRV. The effects of the blending ratio of PSA/FRV on the mechanical properties and the evenness of the yarn were studied. The effects of the blending ratio of PSA/FRV on mechanical properties, flame retardant properties, antistatic properties, moisture permeability and drape of the fabric were analyzed. With the increase of the blending ratios of PSA/FRV, the strength and the elongation of the core-spun yarn increased firstly and then decreased. Moreover, the evenness of the core-spun yarn was improved, the fabric strength increased firstly and then decreased, the flame resistance decreased, and the antistatic performance improved. These results provide an important basis for the preparation and wide application of fabrics made of PSA/FRV/conductive filament.     

Highly stretchable and sensitive strain sensor based on silver nanowires/carbon nanotubes on hair band for human motion detection

In this work, a highly stretchable and sensitive strain sensor using silver nanowires(Ag NWs)/multi-walled carbon nanotubes(MWCNTs) on hair band is proposed. The fabrication process of such sensors enabled scalable and facile production with low cost by dipping hair band into Ag NWs/MWCNTs composites suspension. The sensing performance of the sensors was optimized by tuning the Ag NWs/MWCNTs mass ratio. The hair band based strain sensor with Ag NWs/MWCNTs mass ratio of 30 exhibited the best perf...     

Highly stretchable,sensitive and wide linear responsive fabric-based strain sensors with a self-segregated carbon nanotube (CNT)/Polydimethylsiloxane (PDMS) coating

Flexible strain sensors have received increasing attention with the development of wearable electronic devices. However, integrating wide strain detection range, high sensitivity while maintaining relatively wide linear response range for such sensor system still remain a challenge. A fabric based flexible sensor (S-CNT/PDMS-F) was designed and fabricated, and the sensor can simultaneously achieve high sensitivity, wide linear response and strain detection range by combining self-segregated carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composites and elastic medical bandage. It has been observed that this new sensor system can achieve a high sensitivity with a gauge factor of 615, a large linear responsive range of 0–100% strain (R² ?= ?0.993) and a wide strain detection range of ～ 200%, which is superior to almost all the reported CNT/PDMS flexible strain sensors. Compared to the similar fabric based strain sensor system deploying non self-segregated structure (C-CNT/PDMS-F), our S-CNT/PDMS-F demonstrates higher electrical conductivity and lower electrical percolation threshold and response time of 55 ?ms, as well as more stable and repeatable performance under cyclic loading conditions. The capability of the sensors in monitoring physiological activities and weight distribution has also been demonstrated.     

聚酰胺对水溶液中2，4-二硝基苯酚的吸附行为

研究了聚酰胺树脂吸附水溶液中2，4-二硝基苯酚的性能、条件及其影响因素.结果表明：聚酰胺树脂对2，4-二硝基苯酚具有较强的吸附能力，pH值是影响吸附的主要因素；吸附初段具有较快的动力学速度，中段速率与浓度符合二级反应动力学；吸附过程符合Flundlich 吸附等温式；用1% 氨水溶液可快速完全解吸；吸附过程属于一种基于氢键和范德华力的物理吸附范畴.     

Configuration and capacitance properties of polypyrrole/aligned carbon nanotubes synthesized by electropolymerization

Aligned carbon nanombes(ACNTs) were modified with polypyrrole(PPy) via electropolymerization.Because of the large specific surface area and excellent electrical conductivity of ACNTs,continuous electropolymerization was able to be carried out,forming a thick PPy coating on the ACNTs.The resulting nanocomposite possessed a core-shell structure with ACNTs as the core PPy as the shell,and nanoparticles of PPy on the top,and displayed high performance supercapacitance properties.     

干湿交替对砂岩断裂特性影响试验研究

周期性的水岩相互作用对岩石的物理力学性能有较大的影响,被认为是影响岩土工程安全稳定性的重要因素之一。以典型的均质青砂岩为试验对象,利用中心裂纹圆盘试件开展了砂岩I~II复合型断裂试验,研究了干湿交替作用对砂岩I~II复合型断裂特性的影响;通过观测干湿交替后砂岩微观结构的变化特征,探讨了干湿交替作用的劣化机理;并结合复合型断裂则对试验结果进行了有效评估。研究表明,砂岩的纯I型,纯II型以及I~II复合型断裂韧度均随着干湿交替次数的增加而逐渐减小;其劣化趋势基本一致,但劣化程度略有不同。当加载角较大或II型分量主导时,干湿交替作用对砂岩断裂韧度的劣化影响更为显著。考虑了T应力影响的广义最大周向应变准则和广义最大周向应力准则都能对试验结果进行很好的预测。在纯II型时,基于广义最大周向应变准则的理论预测值比基于广义最大周向应力准则的理论值更接近试验值。     

碳纤维表面阴离子接枝尼龙6对尼龙6等温结晶动力学的影响

利用差示扫描量热仪（DSC）研究了碳纤维（CF）表面阴离子接枝尼龙6（PA6）对CF／PA6复合材料中PA6的等温结晶动力学的影响。结果表明：PA6的等温结晶过程主要为成核作用控制；未接枝的CF对PA6结晶起异相成核作用，提高了PA6的结晶速率；表面阴离子接枝尼龙6的CF对PA6结晶仍起异相成核作用，但由于复合材料的界面相互作用提高，同时又会阻碍PA6分子链的迁移运动，导致表面阴离子接枝PA6的CF／PA6复合材料中PA6组分的结晶速度虽比纯PA6大，但比未接枝PA6的CF／尼龙6复合材料小，且结晶度也有所下降。     

导电海绵-AgNWs复合柔性应力传感器灵敏度优化

以导电海绵为基底,并将其与银纳米线（AgNWs）复合作为柔性电极,制备了一系列柔性应力传感器,其具有良好的灵敏度和重复性.研究发现AgNWs均匀附着在导电海绵的泡沫网络中.受力时随着海绵泡沫结构大形变的同时,AgNWs结构在微观上也产生次级形变,这种多层次的导电网络结构变化有利于增强应力传感器的灵敏度.考察了不同介电材料、介电层厚度、AgNWs滴涂层数等条件对灵敏度的影响,并优化了制备条件,实现了传感器的可控制备.本文制备的传感器制备方法简单,有一定实际应用前景.     

DPD方法模拟嵌段共聚物PP-g-PA6对PP/PA6共混相容性的影响

应用耗散粒子动力学（DPD）模拟方法研究不同共混比PP/PA6的介观相貌及动力学演变过程。加入适量PP-g-PA6后比较研究PP-g-PA6作为相容剂对PP/PA6在不同混合比下相形态的影响,发现在一定混合比下加入少量PP-g-PA6能改变PP/PA6的介观形貌。此外,为研究不同添加量PP-g-PA6对PP/PA6相容性的影响,相对PP和PA6总量分别为2%,4%,6%,8%和10%的PP-g-PA6被加入到90PP/10PA6体系中。结果发现少量的PP-g-PA6能降低共混体系界面张力,提高共混相容性,但是过量的PP-g-PA6会使得体系PA6发生相溶胀从而使体系界面张力变大,不利于体系相相容。     

丁腈橡胶／共聚酰胺共混弹性材料的研究

本文探讨了选用共聚酰胺ＰＡ（ＮＴ－１３０），采用低温混炼工艺所制备的丁腈橡胶／共聚酰胺共混弹性材料的结构及性能。结果表明：该共混材料的相态为两相分离结构；合适的共混比为８０／２０—６０／４０，此时，材料具有高强、高硬度及较高的伸长率和优良的耐摩擦性、耐低温性、耐热油老化性；十腈橡胶与共聚酰胺ＰＡ（ＮＴ－１３０）最适宜的共混温度低于ＰＡ（ＮＴ－１３０）熔点２０－３０℃。