聚氨酯缔合型增稠剂的增稠机理和增稠效率研究

聚氨酯缔合型增稠剂作为一种典型的高分子缔合型增稠剂,在合成制备、增稠效率、增稠机理及刺激响应增稠等方面已经得到了深入的研究。本文综述了近年来国内外有关聚氨酯缔合增稠剂增稠机理和增稠效率影响因素的研究进展,并展望了水性聚氨酯缔合增稠剂的未来研究方向。     

有机高分子缔合型增稠剂的应用及增稠机理研究

介绍了有机高分子增稠剂的种类,疏水改性聚氨酯缔合型增稠剂的增稠机理及在乳液中的应用,综述了近年来国内外有关缔合型增稠剂的科研成果,展望了有机高分子缔合型增稠剂的未来研究方向。聚氨酯缔合增稠剂作为一种典型的高分子缔合型增稠剂,在合成制备、增稠效率、增稠机理及刺激响应增稠等方面已经得到了深入的研究,是未来有机高分子类增稠剂应用的研究方向。     

SMC中不饱和聚酯树脂增稠及贮存性能的研究

本文以甲苯二异氰酸酯（TDI）及其预聚物PU400、PU200为增稠剂对端羟基的不饱和聚酯进行增稠，通过树脂的粘度变化、螺线流动实验对这种新型增稠体系的增稠性能和片材的贮存稳定性进行了研究。并与以MgO为增稠剂的片材进行了对比研究，结果表明：（1）异氰酸酯预聚体的增稠性能优于异氰酸酯单体。（2）增稠剂PU400的质量百分数Wpu应该小于10％。在相同的－NCO浓度下，不饱和聚酯树脂的增稠速度随分子量的提高而加快；在273K下，不饱和聚酯树脂能在4天内完成增稠，在323K下，能在8小时内完成增稠。（3）聚酯片材贮存三个月后，由异氰酸酯增稠体系制备的片材的螺线长度，低于氧化镁增稠体系的下降幅度。     

缔合型聚氨酯增调剂在乳胶涂料中的应用

缔合型聚氨酯增稠剂的许多性能优于其他增稠剂。介绍了该类增稠剂的分子结构、增稠机理和添加方法。讨论了影响聚氨酯增稠剂增稠性的因素。     

乳胶漆中的缔合型增稠剂与乳液作用关系

研究了乳胶漆中非离子缔合型增稠剂对乳液的增稠作用,增稠作用与增稠剂的类型、乳液种类有关.具体研究了4种增稠剂对苯丙、纯丙、醋丙、醋叔乳液的增稠作用.     

缔合增稠剂的制法及影响增稠效果的因素

缔合增稠剂是近年来出现的一种新型增稠剂，因其在水溶液中具有类似表面活性剂的性质以及其独特的增稠作用机理，使其表现出特殊的性质与行为。文中对缔合增稠剂的作用机理、制备方法进行了系统的阐述，着重介绍了影响缔合增稠剂的增稠效果以及缔合增稠剂与水性涂料中其他组分的相互作用，并指出了缔合增稠剂的发展方向。     

新型增稠剂YES在液洗产品中的应用

YES增稠剂是一种阴离子型脂肪醇丙烯酸酯共聚物,专为表面活性剂体系而设计的新型液体增稠剂。对YES的增稠性能、耐盐性、泡沫性能与常用增稠表面活性剂6501、CAB和OA-30等作对比,同时研究了pH值变化以及温度变化对YES增稠剂增稠体系黏度的影响。结果表明,YES增稠剂具有良好的增稠性能和广泛的pH值应用范围,同时具有很好的泡沫性、耐温性和耐盐性。     

不饱和聚酯树脂增稠特性的研究

采用旋转流变仪研究了增稠剂的种类和用量、增稠温度以及填料种类等对不饱和聚酯树脂(uP)增稠体系粘度的影响,分别通过酸值滴定和红外分析等手段探讨了Mgo和MDI的增稠机理,结果表明,四种增稠剂的增稠速度不同,其中MgO最快;增加增稠剂的用量均可加快增稠速度,增稠速度也随增稠温度的增加而加快;填料的加入使得体系的粘度迅速增大.并且不同种类的填料对体系粘度的影响不同,与CaCO3相比,ATH使体系的粘度增加更多.因此工业生产中要综合考虑各方面因素,以获得合适的增稠工艺.     

化妆品用聚丙烯酸类增稠剂的增稠性及耐离子性分析

以5种化妆品常用的聚丙烯酸类增稠剂作为研究对象,通过测试流变学参数黏度对其增稠性及耐离子性进行分析。考察了5种增稠剂水溶液在不同质量分数和pH下的黏度变化,结果表明,共聚物Carbomer 940的增稠效果最好,但黏度在pH=2~11时变化较大;含金属离子共聚物AVS、EMT-10和HMB增稠效果一般,黏度在pH=5~11时保持稳定;自聚物Zen增稠效果最差,但黏度在pH=2~8时保持稳定。向增稠剂水溶液中加入NaCl和MgCl_2,考察化妆品中常见离子对增稠剂水溶液稳定性的影响,结果显示,盐的加入均破坏了5种增稠剂水溶液的稳定性,其中自聚物Zen的耐离子性最好;对增稠性和耐离子性最好的2种增稠剂复配体系进行分析,发现Carbomer 940和Zen的复配体系在增稠性方面起到协同增效的作用,两者复配使用能得到增稠性和耐离子性都较好的增稠剂体系。     

聚氨酯缔合型增稠剂的合成及其应用性能研究

介绍了两款聚氨酯缔合型增稠剂(HEUR)的制备方法,包括一款假塑型增稠剂(增稠剂-万华A)和一款牛顿型增稠剂(增稠剂-万华B),并在乳胶漆配方中考察了这两种增稠剂的增稠性能、配方稳定性、色浆稳定性及展色性;并考察了自制增稠剂B的增稠效率及其在水性木器涂料中的应用。研究表明:合成的自制增稠剂A具有优异的增稠剂效率、良好的配方稳定性、色浆稳定性及展色性。自制增稠剂B具有高效的高剪切增稠效率,在水性木器涂料中性能表现优异,性能良好。     

Application of factorial design to SMC viscosity build-up

Summary The thickening behavior of SMC varies with formulation and operating conditions. During the SMC compounding process, alkaline oxides such as MgO, Mg(OH)₂, CaO, Ca(OH)₂ are added to the formulation to yield the viscosity build-up from a flowable paste to a semi-solid sheet. The thickening curve of SMC can be divided into three stages: 1. The initial thickening period for the wetting process, 2. The middle thickening rate period for viscosity increasing, 3. The final viscosity period for the molding process. By means of factorial design with an appropriate objective set-up, one is able to define the influence of each factor on thickening curves. Combined with the experimental work on some individual factors, the maturation control system can be further understood and the proper thickening rates can be obtained.     

十二烷基硫酸钠碳链分布对PVC糊树脂特性的影响

采用不同种类的市售十二烷基硫酸钠作为乳化剂生产PVC糊树脂,研究了十二烷基硫酸钠的碳链分布对PVC糊树脂粒度分布、糊黏度(B式)、72 h增稠率以及标准糊S流动性的影响,设计出适合PVC糊状树脂生产的配方。     

基于稳态流变测试的水泥浆体剪切模式研究

采用RHEORIAB QC型旋转黏度计测定不同剪切方式下水泥浆体稳态流变曲线,并用修正宾汉姆流变模型对其进行拟合,研究了剪切方式对水泥浆体稳态流变测试的影响.结果表明:预剪切对水泥浆体动态屈服应力和塑性黏度影响不大.恒定剪切变形速率小于、等于、大于、偏大于水泥浆体结构抗剪切破坏能力时,剪切应力随时间分别先线性增加接着保持同一值、直接保持恒定值、先减小接着保持同一值、轻微增加后达到平衡.随剪切速率增加,水泥浆体在0.1～100 s-1、100～400 s-1、400～600 s-1三个区段依次呈现出剪切变稀、宾汉姆流体、剪切增稠的流变行为.剪切速率变化范围向剪切变稀或剪切增稠段移动,水泥浆体动态屈服应力减小、塑性黏度增大;单个剪切速率的剪切时间越长,水泥浆体动态屈服应力、塑性黏度均越小.     

The influence of filler on the emission properties and rheology of carbon nanotube paste

CNT paste consists of organic solution, inorganic binder and filler. Organic solution contains organic resins and solvent including surfactants which finely disperse CNTs. Filler affects surface morphology, electron emission property, viscosity, and rheological characteristics of CNT paste. We used different fillers such as silver and alumina in CNT paste for special function. The emission properties of CNT paste with silver are similar to those of CNT paste with alumina if filler portion is the same. From the scanning electron microscope (SEM) different morphologies of CNTs was observed depending on the type of filler. CNT paste which showed good emission property had vertically well-aligned CNTs on the surface after surface treatment using adhesive tape. We measured viscosity and rheological properties with rheometer RS600 from HAAKE. Emission property of CNT paste was evaluated in vacuum chamber of 10^{− 6} Torr with pulse generator and duty was 1/500.     

Determination of atomistic deformation of tricalcium silicate paste with high-volume fly ash

We examined the effect of incorporating high-volume fly ash on the atomic arrangement and interatomic deformation behavior of calcium silicate hydrates in tricalcium silicate paste upon exposure to external forces. The interatomic structural changes and strains under compressive load were assessed using synchrotron in situ high-energy X-ray scattering-based atomic pair distribution function analysis. Three different types of strains, which were (a) macroscopic strains from gauges on the surfaces of specimen, (b) strains in a reciprocal space (Bragg peak shift), and (c) strains in real space (PDF peak shift), were compared to each other. All monitored and calculated strains for tricalcium silicate-fly ash (50 wt% fly ash) paste were compared with the counterparts of the pure tricalcium silicate paste. Pair distribution function analysis in the range of r < 10 Å indicated that the atomic arrangement of tricalcium silicate-fly ash was similar to that of synthetic calcium silicate hydrates followed by that of pure tricalcium silicate paste. Moreover, the pair distribution function refinement results revealed that the calcium silicate hydrate structure in tricalcium silicate-fly ash paste was similar to tobermorite 11 Å, unlike that in pure tricalcium silicate paste. The interatomic strain of tricalcium silicate-fly ash in the real space (r < 20 Å) was smaller than that of tricalcium silicate under compression, which suggested that the incompressibility of calcium silicate hydrates at atomistic scale was enhanced by the incorporation of fly ash into it. This was likely to be caused by the increased silicate polymerization of calcium silicate hydrates, which was attributed to the increase in the amount of silicate in their structure via the addition of fly ash.     

Surface dispersive energy determined with IGC-ID in anti-graffiti-coated building materials

Coating building materials with anti-graffiti treatments hinders or prevents spray paint adherence by generating low energy surfaces. This paper describes the effect of coating cement paste, lime mortar, granite, limestone and brick with two anti-graffiti agents (a water-base fluoroalkylsiloxane, “Protectosil Antigraffiti^®”, and a Zr ormosil) on the dispersive component of the surface energy of these five construction materials. The agents were rediluted in their respective solvents at concentrations of 5 and 75% and the values were determined with inverse gas chromatography at infinite dilution (IGC-ID).     

超级分散氧化镁对SMC/BMC树脂糊粘度的影响

本文重点研究了在SMC／BMC树脂糊制做过程中超级分散的氧化镁对树脂糊增稠特性的影响。本研究对改进SMC／BMC的成型压力，片材流动，制品质量模塑料的贮存使用期有一定的指导意义。     

Ceramic paste for space stereolithography 3D printing technology in microgravity environment

Additive manufacturing techniques have demonstrated great potential in space manufacturing for long-duration human spaceflight and colonization on alien planets. Herein, we present the design and manufacturing of previously inaccessible complex ceramic components with high precision in a microgravity environment. The proposed approach is based on controlling the rheological properties of ceramic slurry in reduced-gravity. Briefly, HE-cellulose and carbomer 940 are added as thickening agents to transform the ceramic slurry into a ceramic paste(soft matter), which exhibits Bingham pseudoplastic behavior and is not sensitive to gravity variations during parabolic flight. Additionally, X-ray computed tomography (XCT) results reveal that the as-prepared alumina samples, 3D printed in a microgravity environment, render a higher density of 99.3% after sintering. The proposed route can be applied to fabricate complex-shaped ceramic components in space, enabling various possibilities of manufacturing structural and functional materials, including gradient materials, solid fuel cells, active insulation ceramic structures and piezoelectric sensors.     

Modeling the linear elastic properties of Portland cement paste

The linear elastic moduli of cement paste are key parameters, along with the cement paste compressive and tensile strengths, for characterizing the mechanical response of mortar and concrete. Predicting these moduli is difficult, as these materials are random, complex, multi-scale composites. This paper describes how finite element procedures combined with knowledge of individual phase moduli are used, in combination with a cement paste microstructure development model, to quantitatively predict elastic moduli as a function of degree of hydration, as measured by loss on ignition. Comparison between model predictions and experimental results are good for degrees of hydration of 50% or greater, for a range of water : cement ratios. At early ages, the resolution of the typical 100³ digital microstructure is inadequate to give accurate results for the tenuous cement paste microstructure that exists at low degrees of hydration. Elastic computations were made on higher resolution microstructures, up to 400³, and compared to early age elastic moduli data. Increasing agreement with experiment was seen as the resolution increased, even when ignoring possible viscoelastic effects.