开孔剂GK-350D在高回弹聚氨酯软质泡沫中的应用

采用多元醇、甲苯二异氰酸酯和自制的开孔剂GK-350D制备了密度为32～35 kg/m3的聚醚型高回弹聚氨酯软质泡沫。用FoamatLR2-40 PFT型测定仪跟踪了泡沫的发泡过程,从其发泡曲线上求取了泡沫开孔后的下沉率,表征了开孔剂在泡沫中的开孔能力。结果表明,GK-350D用量为1.2份时,具有较高的开孔能力,开孔性能与国际同类产品水平相当,且没有影响聚氨酯泡沫制品的性能。     

聚氨酯发泡工艺中使用的时间控制器

1概述多年来，由于冰箱、空调、家具、玩具、室内装饰等行业的发展，聚氨酯泡沫塑料制品的市场需求飞速增长，各地的泡沫生产厂家大量涌现。为了能生产出性能稳定、品质优良的泡沫产品，在发泡过程中常常采用手工调整泡沫配方，科研工作中也常用到手工发泡。下面向大家介绍一种手工发泡控制器《SJ－Ⅰ》型定时器，也许会有帮助。不同的聚氨酯泡沫塑料制品，对所用泡沫的性能要求是不同的。各种性能的泡沫所用原料的配方千差万别、各式各样。配方的选择有很多重要的依据，其中一条就是要求准确掌握发泡过程中各个阶段的时间。聚氨酯发泡整个…     

聚氨酯发泡剂的研究进展

聚氨酯发泡技术是当前聚氨酯工业领域中的研究热点,而所使用的发泡剂必须符合环保法规并且与聚氨酯泡沫材料性能密切相关。因此,发泡剂的研究和选择成为人们关注的重点。论文综述了物理发泡剂和化学发泡剂的研究进展以及它们在聚氨酯工业中的应用情况,重点介绍了新型化学发泡剂"碳酸醇胺盐"及其优点,提出了针对采用发泡剂"碳酸醇胺盐"的发泡配方、发泡剂本身的生产工艺以及生产泡沫材料的发泡工艺开展进一步研究的建议。     

全水低密度超柔软块状聚氨酯软泡技术研究

通过降低TDI指数的方法,全水发泡,制备了低密度超柔软聚氨酯泡沫,制得的密度为17～19kg／m^3的泡沫,25％压陷硬度小于50N。对泡沫制备过程的各种影响因素及影响泡沫性能的因素进行了详细的讨论。     

PF/PDMS-OH流变性能对其泡沫材料泡孔结构的影响

分别将质量分数为10%,15%和20%的端羟基聚硅氧烷(PDMS–OH)通过机械共混的方法改性酚醛树脂(PF),进而采用化学发泡的方法制备PF/PDMS–OH泡沫复合材料。采用旋转式流变仪表征共混体系的稳态及动态流变性能,研究黏弹性对树脂发泡过程的影响。傅立叶变换红外光谱表征PDMS–OH与树脂在固化过程中的化学反应。扫描电镜表征不同共混体系下泡孔的结构与形态。结果表明,加入15%PDMS–OH的共混体系具有最利于发泡成型的黏弹性,且可与PF形成化学交联作用,对PF泡沫的泡孔形态影响显著。同时红外表征显示,PDMS–OH与PF在固化过程中发生化学交联,这种互穿交联网状结构为PF及泡沫提供了更多稳定的柔性链段。     

高吸油性能软质聚氨酯泡沫的合成研究

以聚醚多元醇(N220、N330)和甲苯二异氰酸酯(TDI)为原料,采用一步发泡法,合成一种泡沫质地柔软、泡孔结构较好、且具有较高吸油性能的软质聚氨酯泡沫。研究了催化体系、TDI指数、物理发泡剂、聚醚多元醇、水、泡沫稳定剂等对泡孔结构和吸油性能的影响。得到了最佳工艺配方,即:聚醚多元醇100份,TDI指数103%,A33为4.8份,辛酸亚锡(T9)0.8份,泡沫稳定剂为4份,物理发泡剂(141b)20份,水10份。制得的泡沫结构较好时,对原油的吸油倍率为35 g/g。     

利用废玻璃研制泡沫玻璃

利用回收的废玻璃为泡沫玻璃为主要原料,添加少量的发泡剂和一些其它化工原料,采用低温（７６０～８１０℃）发泡工艺,探讨了配合料的配方组成和不同的发泡工艺制度对泡沫玻璃性能的影响。通过比较,得出了合理的泡沫玻璃的配方及发泡工艺制度;试制出的泡沫玻璃具有容重低、抗压强度,烧成周期短,易于控制的特点。     

冷熟化高回弹聚氨酯模塑泡沫的制备

开发了基于ＴＥＰ３０３３、二乙醇胺和ＴＭ８０的全水发泡低密度、低硬度冷熟化高回弹聚氨酯模塑泡沫配方，研究了配方中主要原料对发泡配方的影响。在本研究配方条件下，使用复合胺类催化剂可得到良好的制品表现和泡沫加工性，且改善了表皮质量。     

有机硅泡沫材料的制备及性能研究进展

有机硅泡沫材料因独特的无机-有机杂化结构使其具有良好的阻燃性能、耐高低温性能、化学稳定性,又因含有大量泡孔结构而具有缓冲减震、质量小、隔音隔热、吸声等优良特性,被广泛应用于生物医学、航天航空、电子设备等领域。有机硅泡沫材料的制备方法有化学发泡法(内发泡法和外加发泡剂法)、物理发泡法(3D打印法、溶析成孔法和惰性气体法)、模具法、辐射交联法、混合发泡法等多种方法。随着对有机硅泡沫材料研究的不断深入,绿色化、功能化和低成本将是其未来研究的重要方向。     

泡沫稳定剂对丙烯酸酯胶黏剂发泡体系的影响

阐述了泡沫体系的稳泡机理,采用物理发泡方法,研究了不同种类、含量的泡沫稳定剂对丙烯酸酯胶黏剂发泡体系的影响。结果表明,有机硅AK8805对该体系的效果最好。当发泡剂含量为15%、有机硅AK8805的含量为9%时,该发泡体系的发泡倍率可达到43.6 ml.g-1。     

Modification of PUR-PIR foams by boroorganic compound prepared on the basis of di(hydroxymethyl)urea

The method for preparation of boroorganic compound with application of N,N′-di(methyleneoxy-3-hydroxypropyl)urea and boric acid has been described. Then, the borate prepared was characterized mainly in the terms of its usability as a polyol component and fire retardant for production of the rigid polyurethane-polyisocyanurate foams. Method of preparation, the determination of foaming parameters, physicomechanical and fire properties of PUR-PIR foams as well as the results of tests have been presented. The recipe for foam preparation was modified by application of physical and chemical method of foaming. On the basis of the results, it was found that application of the new compound in recipe for production of foams is very favourable. The rigid foams obtained are characterized by lower brittleness, higher compressive strength, lower thermal conductivity and considerably lower flammability in comparison with a standard foam.     

Structures and physical properties of rigid polyurethane foam prepared with rosin‐based polyol

Rosin‐based polyester polyols were synthesized from a rosin–maleic anhydride adduct, diethylene glycol, and ethylene glycol with and without adding adipic acid and phthelic anhydride, in the presence of catalyst. Rigid polyurethane (PU) foams were prepared with these rosin‐based polyols and compared with foam made with an industrial polyester Daltolac? P744. The experimental results show that the foaming behavior for the foams prepared from such rosin‐based polyols is similar to that of industrial products, but their 10% compression strength, both parallel and vertical to foaming rise direction, is higher and the dimensional stability at 100 and ?30°C is similar or somewhat better than that of a comparable system. Furthermore, the rosin‐modified PU foams exhibit even lower thermal conductivity and much higher activation energies during the pyrolysis process. All these unique physical properties of the rosin‐modified rigid PU foams were correlated to the structures of these PU foams. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 598–604, 2002; DOI 10.1002/app.10312     

New compounds for production of polyurethane foams

A method of boroorganic compound preparation with boric acid, 1,3‐propanediol, 2,3‐butanediol, and 1,4‐butanediol is described in this article. The obtained compounds were characterized with respect to their usability as polyol components for the production of polyurethane (PUR) foams. New boroorganic compounds were applied as polyol components for the foaming of rigid PUR–polyisocyanurate (PIR) foams. The method of preparation, foaming parameters, and physicochemical properties of the PUR–PIR foams and their results are presented. Application of the prepared borates as polyol components in the production of foams had a favorable effect on the properties of the foams. The obtained rigid foams were characterized by lower brittleness, higher compressive strength, content of closed cells, and considerably reduced flammability in comparison with standard foams. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5918–5926, 2006     

Carbon foams with high compressive strength derived from mixtures of mesocarbon microbeads and mesophase pitch

Carbon foam with relatively high compressive strength and suitable thermal conductivity was prepared from mixtures of mesocarbon microbeads (MCMBs) and mesophase pitch, followed by foaming, carbonization and graphitization. The influence of addition amount of MCMB on the properties of as-prepared carbon foams was investigated in detail. Results showed that addition of MCMBs into mesophase pitch could significantly reduce the amount and length of cracks in carbon foams, which results in increase of compressive strength of carbon foams. Carbon foam with high compressive strength of 23.7 MPa and suitable thermal conductivity of 43.7 W/mK, was obtained by adding 50% MCMBs into mesophase pitch, followed by foaming, carbonization and graphitization.     

Microcellular foaming of silicone rubber with supercritical carbon dioxide

In spite of great concern on the industrial application of microcellular silicone rubber foams, such as in electric and medical devices, only a few works can be found about the foaming of silicone rubber. In this study, microcellular silicone rubber foams with a cell size of 12 μm were successfully prepared with curing by heat and foaming by supercritical CO₂ as a green blowing agent. The microcellular silicone rubber foams exhibited a well-defined cell structure and a uniform cell size distribution. The crosslinking and foaming of silicone rubber was carried out separately. After foaming, the silicone rubber foam was cross-linked again to stabilize the foam structure and further improve its mechanical properties. Foaming process of cross-linked silicone rubber should be designed carefully based on the viscoelastic properties because of its elastic volume recovery in the atmosphere. The basic crosslinking condition for small cell size and high cell density was obtained after investigating the rheological behavior during crosslinking.     

聚合物多元醇GPOP-H45制备高回弹泡沫研究

采用新型高活性聚合物多元醇GPOP-H45为原料,制备出机械性能良好的高回弹泡沫制品。讨论了影响泡沫性能的主要因素及国外同类产品发泡情况和制品性能的比较。结果发现,在发泡中加入GPOP-H45,可显著提高泡沫制品的承载性及开孔性,同时改进了其机械性能。     

Conductive Ceramic Foams from Preceramic Polymers

Ceramic foams in the system Si-O-C, possessing different bulk densities and morphologies, were obtained from preceramic polymers using two different direct foaming approaches. The electric properties of the foams were varied by adding suitable fillers to the precursor mixtures in amounts up to 80 wt%. The electrical conductivity of the foams was varied by several orders of magnitude. The effects of the type of filler and preceramic polymer (methylsiloxane or methylphenylsiloxane resins), as well as the used filler precursor, on the properties of the ceramic foams were investigated.     

环境友好型阻燃高回弹聚氨酯软泡性能

开发环境友好型聚氨酯是目前聚氨酯（polyurethane,PU）泡沫塑料领域的热点课题。在PU中引入大豆分离蛋白质（soy protein isolate,SPI）,采用阻燃聚醚制备了环境友好型阻燃高回弹聚氨酯软泡。研究了SPI的不同添加方式及用量对聚氨酯软泡物理、力学、阻燃和生物降解性能的影响。结果表明,SPI以添加的方式而不是替代聚醚的方式加入软泡性能更好;少量添加SPI可以提高PU软泡的开孔率、密度、压陷硬度、舒适因子、回弹率和断裂伸长率,对压缩永久变形率、拉伸强度和极限氧指数影响不大。SPI改变了PU的硬段结构,可以有效促进聚氨酯泡沫的生物降解。     

Preparation of carbon foams with supercritical toluene

Carbon foams with pore sizes of 10–50 μm were prepared with mesophase pitch and toluene as the carbonaceous precursor and supercritical agent, respectively. Results revealed that the light pitch components and dissolved toluene in pitch significantly affected the pore structures of resultant carbon foams. The amount of toluene dissolved in molten pitch is greatly dependent on the foaming conditions, such as the ratio of toluene to pitch, foaming temperature, foaming pressure and saturation time. Carbon foams with hierarchical porous structures are obtained by controlling the amount of light pitch components.