聚氨酯泡沫用有机硅匀泡剂的合成及应用探讨

对当前匀泡剂的发展进行了分析,针对有机硅匀泡剂在聚氨酯泡沫生产中发挥的作用以及实际应用特点进行了探讨。结合实际状况对我国聚氨酯泡沫合成中有机硅匀泡剂的应用发展提出了一些建议。     

大型模胎用硬质聚氨酯泡沫塑料的制备研究

研究了大型模胎用硬质聚氨酯泡沫塑料的制备方法,考察了催化剂用量、匀泡剂用量、物理发泡剂用量、化学发泡剂、模具压力、后处理温度等对硬质聚氨酯泡沫塑料泡体结构和性能的影响。结果表明,可以通过控制催化剂三乙醇胺和有机锡的用量配比来调节发泡和凝胶速率,匀泡剂用量、物理发泡剂用量、化学发泡剂、模具压力、后处理温度等均能对泡体结构和性能产生影响。     

有机硅匀泡剂在聚氨酯硬泡中的应用评价

比较了添加自制有机硅匀泡剂与国内外主流匀泡剂的聚醚组合料的乳化性能和流动性能,及其聚氨酯硬泡的吸水率和尺寸稳定性。结果表明,对于环戊烷发泡体系,添加自制有机硅匀泡剂XHG-295和国内外主流匀泡剂的聚醚组合料的乳化性能和流动性能及其聚氨酯硬泡的吸水率和尺寸稳定性都接近;对于HCFC-141b发泡体系,添加自制有机硅匀泡剂XHG-299和国内外主流匀泡剂的聚醚组合料的乳化性能和流动性能及其聚氨酯硬泡的吸水率和尺寸稳定性都接近。XHG-295和XHG-299能达到家电组合料和保温板材组合料生产对匀泡剂的质量要求。     

硅碳型软泡匀泡剂合成及其性能研究

对一种醚基封端硅碳型聚氨酯软泡匀泡剂Ｈ－４２０的合成，发泡性能进行了研究并与同类匀泡剂比较性能。结果表明，在结构上它与美国Ｌ－５８０匀泡剂属同一类型，发泡性能也与Ｌ－５８０相近。     

软泡匀泡剂D-529的合成及其性能研究

以含氢硅油与不饱和聚醚的硅氢加成反应合成了软泡匀泡剂D-529,并对这种醚基封端的硅碳型聚氨酯软泡匀泡剂D-529的合成及其某些性能进行了研究。结果表明,在结构上与美国L-580匀泡剂属同一类型,发泡性能与L-580相似,并且用量小、活性高。     

Si—C型聚氨酯匀泡剂的合成研究

首先针对Si—C型聚氨酯匀泡剂的结构以及相对应的性质进行简单阐述。其次,与实际情况进行结合,提出Si—C型聚氨酯匀泡剂在具体合成过程中的路线。     

低挥发有机硅匀泡剂在聚氨酯软泡中的应用评价

研究了4种有机硅匀泡剂对聚氨酯软泡中的挥发性有机化合物(VOC)和泡沫性能的影响。结果表明,采用相同的配方,与同类匀泡剂相比,分别使用低散发性匀泡剂BL-585LF和BL-8008NA制备的聚氨酯普通软泡和慢回弹泡沫具有较低的VOC、更好的舒适性和压缩永久变形,并且制得的普通软泡有更好的回弹性。     

聚氨酯有机硅匀泡剂的研究及应用

综述了近年来有机硅表面活性剂聚二甲基硅氧烷、聚醚改性聚硅氧烷作为聚氨酯泡沫塑料匀泡剂的研究进展,重点介绍了其主要品种S i─C型聚醚改性聚硅氧烷在无溶剂工艺、催化剂的制备及聚醚配方优化等方面的进展,指出目前提高国产软泡匀泡剂的产品质量是聚氨酯有机硅匀泡剂研究的发展方向。     

粗孔匀泡剂HRSi-2在聚氨酯软泡中的应用

介绍了粗孔匀泡剂HRSi-2应用于普通软泡体系中,制备类似于高回弹泡沫制品的技术。对使用HRSi-2、普通软泡匀泡剂G-580及高回弹匀泡剂WD5333制备的相同密度的软质聚氨酯泡沫制品及高回弹泡沫制品的外观和泡沫性能进行了对比。结果表明,采用粗孔匀泡剂HRSi-2的聚氨酯软泡制品具有高回弹软泡的粗孔、乱孔的特点,综合性能介于普通软泡与高回弹软泡之间。     

投产鉴定

软质聚氨酯泡沫塑料用匀泡剂投产 最近,年产1000吨软质聚氨酯泡沫塑料用匀泡剂——丙烯醇聚氧丙烯聚氧乙烯无规共聚物(DHY-2)在东营达仕化工有限公司投产。该产品的开发和生产填补了国内软质聚氨酯泡沫塑料(海绵)用匀泡剂生产的空白,该产品广泛应用于海绵、高回弹及高活性聚氨酯泡沫塑料等工业产品的生产工艺中,市场需求量大。     

Influence of dialkyl ethers on the surface properties of homogeneous nonionic surfactants

Influence of the trace amounts of the corresponding dialkylethers on the surface and colloidal properties of the pure polyoxyethylene alkyl ethers were studied. The dialkyl ether, undetected by gas liquid chromatography (GLC) was found by gel permeation chromatogram (GPC) as the corresponding impurity in homogeneous pure polyoxyethylene alkyl ether and confirmed using infrared (IR), nuclear magnetic resonance (NMR) and mass spectroscopy (MS). After removing the corresponding impurity in each surfactant with a GPC separation column, the minima in the surface tension curves disappeared completely. Adding the corresponding dialkyl ether to the pure surfactant produced the minima in the surface tension curves and large values for surface aging, cloud points were lowered more than for the pure surfactants and foam height and foam stability for the aqueous solutions decreased gradually.     

乳状液膜用表面活性剂TH-1的合成与性能研究

本课题研究了适用于乳状液膜法的一种聚胺类高分子表面活性剂的合成及性能。采用红外吸收光谱和凝胶色谱法对高分子原材料和合成过程的中间体及表面活性剂产物进行了分析试验。实验结果表明：由它制成的乳状液稳定性好、耐酸碱、溶涨率低，是一种性能优良适合于乳状液膜用的表面活性剂。     

AKD专用高分子表面活性剂的性能研究

设计并合成了一种高分子表面活性剂,用FTIR、DSC、GPC分析手段研究了高分子表面活性剂的分子结构,并对其表面张力进行了测定。测试结果显示,4种单体都参与了共聚反应,无均聚物存在,高分子表面活性剂的重均分子量为58 536,数均分子量为16 812,多分散性系数为3.48,说明相对分子质量(简称分子量)的分散程度较小。温度为25℃时,高分子表面活性剂的CMC为0.8 mmol/L,γCMC为50.1 mN/m。当m(高分子表面活性剂)/m(烯酮二聚体)=0.23时,可制备出稳定的烯酮二聚体(AKD)乳液,且该AKD乳液质量占绝干浆质量的0.13%时,浆内施胶度可达200 s以上。用马尔文纳米粒度及Zeta电位分析仪测定出AKD乳液的平均粒径为574.4 nm,Zeta电位为11.16 mV。通过TEM观察,AKD乳胶粒子在高分子表面活性剂的包裹下呈核壳结构,并且形成水包油乳液。该高分子表面活性剂具有良好的表面活性与应用潜力。     

用于平版成像的改性PVA树脂合成和表征

采用3种不同型号聚乙烯醇(PVA)通过缩醛和与酸酐酯化两步反应合成了含羧基的聚乙烯醇缩丁醛树脂(PVB-PA),通过1H-NMR、GPC和FTIR等方法对改性产物进行了表征。结果表明:缩醛反应中,当盐酸的质量分数为1.3%~5.6%(以PVA计),以十二烷基硫酸钠为表面活性剂,四正丁基溴化铵为相转移催化剂时,可合成缩醛度为40%~80%的聚乙烯醇缩丁醛树脂(PVB)。PVB的实际缩醛度与设计缩醛度基本一致,PVB溶解性随缩醛度变化而变化。酯化反应中,选择醋酸作溶剂,醋酸钠作催化剂,反应结束时应先加入一定量的甲醇。PVB-PA的实际酯化度是设计酯化度的1/2,缩醛度较酯化前有5%~10%的下降。缩醛度39%~76%,酯化度9%~21%的PVB-PA在乙二醇独甲醚、丁酮及显影液中溶解性较好,可用于平板成像体系。     

Synthesis,characterization, and properties of amphiphilic block copolymer of acrylamide‐styrene by self‐emulsifying microemulsion method

The copolymerization system of acrylamide (AM) and styrene (St) was acquired by using amphiphilic block copolymer PAM‐b‐PSt with lower molecular weight as polymeric surfactant, and then the microemulsion phase diagram was drawn. The appropriate copolymerization systems were chosen in the phase diagram, and higher molecular weight amphiphilic block copolymers PAM‐b‐PSt were prepared by self‐emulsifying microemulsion method. The chemical composition and structure of the products were analyzed by FTIR, ¹H‐NMR, ¹³C‐NMR, GPC, and UV; the block structure of products was characterized by DSC, and the hydrophobic association property of the products was studied by the fluorescence probe and rotating viscosity measurement. The results showed that O/W microemulsion was also acquired by using the polymeric surfactant; 3 g polymeric surfactant was only used to disperse 0.25 g St into aqueous solution, which showed higher emulsifying efficiency. At the same time, the use of self‐emulsifying microemulsion copolymerizing system can avoid back treatment of small molecular surfactant and the purified block polymer was prepared in one step; the prepared copolymers have good hydrophobic association properties and their aqueous solution showed evident viscosity increment. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Measurement of molecular weight of poly(vinyl chloride)

Molecular weights of six bulk-process and five suspension-process PVC samples have been measured as part of a study aimed at developing a technique for gel permeation-chromatographic analysis of this polymer in tetrahydrofuran at room temperature. Osmometric M?_n values measured in cyclohexanone appear to be valid; the results are insensitive to thermal history or ultrasonic irradiation of the solution. Corresponding measurements in tetrahydrofuran changed with measurement temperature and indicated the presence of stable supermolecular PVC aggregates in this solvent. Such aggregates can be dispersed by ultrasonic treatment of the solution for brief periods. Simultaneous degradation of PVC molecules appears to be prevented by addition of small concentrations of nonionic surfactant to the tetrahydrofuran solutions. Treated solutions are suitable for GPC analyses at ambient temperatures. The results of osmometry, light scattering, and GPC agreed well.     

Surfactants from Recycled Poly (ethylene terephthalate) Waste as Water Based Oil Spill Dispersants

Recycled poly (ethylene terephthalate), PET, can be modified to produce nonionic surfactants. Recycling of PET waste was carried out in presence of different weight ratios of diethanolamine and triethanolamine and manganese acetate as catalyst. The molecular weights of the prepared oligomers were calculated from hydroxyl number and determined from GPC measurements. The produced oligomers were reacted with polyethylene glycol, PEG, which have different molecular weights 400, 1000 and 4000. Interfacial tension and the effectiveness in oil dispersion of the synthesized surfactants were reported. It was found that, the maximum efficiency of oil spill dispersants was reached to maximum when the surfactant molecules ended with two PEG 1000 moities.     

Synthesis of oligomer vinyl acetate with different topologies by RAFT/MADIX method and their phase behaviour in supercritical carbon dioxide

Poly(vinyl acetate) (PVAc) has been shown to exhibit anomalously high solubility in CO₂ as compared to other vinyl hydrocarbon polymers. Understanding the phase behaviour of PVAc with different topologies in CO₂ is very important for its potential applications as suitable surfactant, or phase transfer agent in a CO₂ solvent process. In this study, a series of PVAcs with different topologies (bi-arms, tri-arms, tetra-arms) were synthesized by RAFT/MADIX method. The structures and molecular weights of these polymers were characterized by ¹H NMR and GPC. The phase behaviours of PVAcs in dense carbon dioxide fluid were determined, and the results show that the PVAc with more arms has lower cloud point pressure.     

Characterization of bisphenol A–based epoxy resins by HPLC,GPC, GPC–MALLS,VPO, viscometry,and end group analysis: On the identification of 2,3‐dihydroxypropyl‐containing compounds,determination of molar mass distribution,and branching

Reversed‐phase high performance liquid chromatography (HPLC), conventional gel permeation chromatography (GPC), and gel permeation chromatography coupled with a multiangle laser light scattering photometer (GPC–MALLS) were used for the analysis of epoxy resins based on bisphenol A. Compounds containing 2,3‐dihydroxypropyl group were identified in HPLC chromatograms by means of the derivatization of sample by acetone. The presence of branched molecules was proved by GPC–MALLS using a molar mass versus root mean square (RMS) radius plot or molar mass versus elution volume plot. The molar mass distribution determined by HPLC was compared with that obtained by GPC–MALLS. Molar mass averages measured by means of GPC, GPC–MALLS, vapor pressure osmometry (VPO), and end group analysis (EG) were compared and the differences of results obtained by particular methods were discussed. An appropriate GPC calibration was found on the basis of literature data and the comparison of molar mass averages measured by GPC, VPO, and GPC–MALLS. The refractive index increment of epoxy resins was determined. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2432–2438, 1999     

Enzymatic synthesis of soluble phenol polymer in water using anionic surfactant as additive

In phosphate–citric acid buffer (pH = 8.0) containing sodium dodecylbenzenesulfonate (SDBS) as a surfactant, enzymatic polymerization of phenol catalyzed by horseradish peroxidase (HRP) is efficiently performed. The as‐synthesized phenol polymer is completely soluble in organic solvents such as dimethylfomamide, dimethylsulfoxide, acetone and tetrahydrofuran. The aqueous micelle system provides a new environmentally friendly method for HRP‐catalyzed phenol polymerization. The effects of the dosage of SDBS and reaction temperature on the yield of the target phenol polymer are investigated. The soluble phenol polymer is composed of phenylene and oxyphenylene units as determined using infrared and ¹ H NMR spectral analyses. The number‐average molecular weight calculated from gel permeation chromatography (GPC) is in the range 900–1500 g mol^?1 and the dispersity in the range 3.4–6.3. In all cases, the values of weight‐average molecular weight characterized using GPC–static light scattering are tens of thousands. It is concluded that a branched structure is produced in the aqueous micelle system. The phenol polymer prepared possesses good thermal stability for it is completely decomposed at a temperature as high as 628 °C in air.