聚氨酯硬泡用阻燃多元醇制备路线综述

根据所含阻燃元素的不同,聚氨酯硬泡用阻燃多元醇大致可分为磷系阻燃多元醇、卤系阻燃多元醇、复合型阻燃多元醇及芳杂环类阻燃多元醇等。本文对各种类型多元醇的制备路线进行了总结,并介绍了几种具有代表性的合成方法。     

Kraft Lignin-Based Rigid Polyurethane Foam

Abstract

Kraft pine lignin was derivatized to a liquid polyol through oxypropylation. The resulting polyol was characterized by GPC, FT-IR, H¹, C¹³, and P³¹ NMR and was compared to commercial polyols in view of the mechanical property of the corresponding rigid polyurethane foams for the first time. A series of lignin-based PU was synthesized by replacing varying weight percentages of the amount of sucrose polyol and glycerol polyol, two commonly used commercial polyols employed in the control foam preparation. All foams had a low density of ～30 Kg m^?3 and showed typical linkages of PU in the FT-IR spectra. The diameter of closed-cells was ～650 μm for most of the foams as revealed by SEM images. The optimal compressive property of rigid PU foams was obtained using lignin polyol without the addition of any other commercial polyols primarily attributed to the rigidity of lignin aromatic structure and the high functionality of lignin hydroxyl groups.     

The Combustion of Rigid Polyurethane Foams

Abstract

The effect of the porous structure on the flammability characteristics of rigid polyurethane foams is studied. It is found that the velocity of the downward flame spread over the surface of foam slabs increases as the oxygen content into the ambient flow increases and the effective density of PU foams decreases.

The measurements of temperature profiles into the combustion wave made by Pt-PtRh thermocouples are used for the determination of the rate-controlling energy-transfer mechanisms.     

全水发泡硬质聚氨酯泡沫塑料的研制

研制了低粘度的聚醚PE600系列和具有良好流动性的全水发泡硬质聚氨酯泡沫塑料组合聚醚。对制备中影响发泡性能的有关因素进行了探讨。依此制备的硬质聚氨酯泡沫塑料具有良好的尺寸稳定性、优异的粘接性能和较低的导热系数，已达到或超过汽车、建筑行业对全氟泡沫的要求，具有广阔的市场前景。     

可膨胀石墨在硬质聚氨酯泡沫阻燃性能中的研究

对近年出现的一种新型膨胀阻燃剂———可膨胀石墨(EG)在硬质聚氨酯泡沫塑料(RPUF)中的阻燃性能与其它几种无卤阻燃剂作了比较。用氧指数(LOI)法研究了EG与聚磷酸铵(APP)、磷酸三乙酯(TEP)、三聚氰胺(MA)、三聚氰胺氰脲酸盐(MC)等无卤阻燃剂在RPUF中的协同阻燃作用。结果表明,EG阻燃RPUF的效果最好;并且EG与这些无卤阻燃剂之间存在着协同或反协同作用,其中EG与两种含磷阻燃剂APP和TEP的协同效果最好。     

植物油多元醇的制备及其在聚氨酯硬泡中的应用进展

综述了植物油的特性、植物油多元醇的合成工艺以及最新的研究进展。介绍了国内外聚氨酯硬泡的发展趋势以及改性植物油多元醇在聚氨酯硬泡方面的应用研究进展。概述了国内外近年来在植物油多元醇工业化方面的情况。     

以生物质为原料制备聚氨酯泡沫塑料的研究进展

主要介绍了目前国内外利用淀粉、松香、植物油、纤维素、木质素等生物质原料用于合成聚氨酯泡沫塑料的研究进展。以生物质替代石化原料,可以改善聚氨酯泡沫塑料生物降解性等性能,可降低产品生产成本,提高市场竞争力。     

废旧聚氨酯硬质泡沫塑料的降解回收及再利用

采用双组分醇解剂乙二醇（EG）和丙二醇（PG）对废旧聚氨酯（PU）硬质泡沫塑料进行降解,获得了降解产物低聚物多元醇,并将其与木质素为原料制备出再生聚氨酯（r?PU）硬质泡沫塑料复合材料。利用导热系数测定仪、扫描电子显微镜、热重分析仪、傅里叶变换红外光谱仪等对废旧PU的降解效果和r?PU硬质泡沫复合材料的压缩强度、吸水率、导热系数、微观形貌及热稳定性等进行了分析和表征。结果表明,双组分醇解剂EG和PG质量比（m_EG：m_PG）为2：3时,废旧PU的降解效果最佳;当木质素添加量为6 %（质量分数,下同）时制备r?PU硬质泡沫复合材料的泡沫孔壁较厚且比较均匀,骨架几何构型完整,其压缩强度为185.3 kPa、导热系数为0.021 5 W/（m·K）,均能够达到国家标准要求。     

应用于建筑工业的硬质聚氨酯泡沫塑料(续)

将泡沫喷涂到用织物增强PVC制作的半圆形充气气球上．反应混合物立即发泡,可以按照设计的厚度喷涂几次泡沫达到设定厚度后放气,再按需要切出门窗即可。可以代替帐篷,有好的绝热性能、机械稳定性和耐用性,屋顶直径可达5m。     

Thermal Stability and Flame Retardancy of Rigid Polyurethane Foams/Organoclay Nanocomposites

The thermal stability and flame retardancy of a new kind of rigid polyurethane (PU) foams/organoclay nanocomposites developed by our research group were investigated by using thermogravimetry analysis (TGA) and cone calorimeter test. Results indicate that compared with pure PU foams, rigid PU foams/organoclay composites show significantly enhanced thermal stability and flame retardancy. The reasons leading to the results were discussed in detail by relating with the morphology of the composites. The discussion suggests that the enhancement degree of thermal stability and flame retardancy of composites compared with that of PU foams coincides well with the sequences of gallery spacing of organoclay in the PU matrix.     

新型疏水聚氨酯硬质泡沫的绿色制备及其性能研究

采用半预聚法作为发泡工艺,以全氟聚醚作为一种新型泡沫稳定剂,选用水作为绿色化学发泡剂,制备了疏水型聚氨酯硬质泡沫.结果表明,随着全氟聚醚含量的增加,材料的接触角增大,最高可达139.7°;添加全氟聚醚后,其泡沫具有较高的闭孔率,而且随着全氟聚醚含量的增加,泡孔更加均匀,泡孔尺寸逐渐减小,泡孔的密度增大,导热系数显著降低...     

生物降解型聚氨酯泡沫塑料用低聚多元醇的研究进展

阐述了国内外可生物降解聚氨酯材料的发展概况,重点介绍了采用植物油、二氧化碳、纤维素、淀粉等原料制备可生物降解型聚氨酯泡沫塑料用低聚多元醇方法及以零ODP发泡剂制备的可生物降解型聚氨酯泡沫塑料,讨论了它们的应用及发展趋势。     

Chemical Modification of Methanol-Insoluble Kraft Lignin Using Oxypropylation Under Mild Conditions for the Preparation of Bio-Polyester

Methanol-insoluble high-molecular weight (M_w = 26,610 g mol^?1) soft wood kraft lignin was oxypropylated under the mild condition of 40°C and 1 atm for 12 h in the presence of NaOH catalyst for the production of bio-polyester. Fourier transform infrared spectra showed that polyether chains were extended due to the oxypropylation reaction. The M_w and M_n of the oxypropylated lignin were 46,330 and 17,110 g mol^?1, respectively. The high-molecular weight oxypropylated lignin was reacted with sebacic acid or polybutadiene (dicarboxy terminated) for bio-polyester synthesis. While the decomposition temperatures of the oxypropylated lignin were 217°C and 367°C, those of the bio-polyesters prepared with sebacic acid and polybutadiene (dicarboxy terminated) were 380°C and 453°C, respectively, indicating that the bio-polyesters possessed enhanced thermal properties. The oxypropylation of methanol-insoluble high-molecular weight lignin under mild conditions is one of the promising approaches for preparing bio-plastics with an enhanced thermal property.     

难燃聚氨酯软质泡沫的制备及性能研究

用新型难燃接枝聚合物聚醚多元醇和聚醚多元醇3050的混合物与甲苯二异氰酸酯(TDI)自由发泡反应，制备了阻燃型聚氨酯软质泡沫。讨论了难燃接枝聚合物聚醚多元醇的用量对聚氨酯软质泡沫密度、氧指数和力学性能的影响。结果表明，随着难燃聚醚用量的增加，聚氨酯软质泡沫的阻燃性能提高，力学性能也有显著提高，泡沫体的密度降低。     

Polyurethane Foams of Improved Thermal Stability

In reactions of polyetherols prepared from hydroxymethyl derivatives of uric acid and typical oxiranes with isocyanates and water one obtains a new group of polyurethane foams containing purine rings in their structure. These polyurethanes withstand prolonged heating at temperatures as high as 200 °C. Preliminary results on the effect of the type of polyetherol and the composition used in preparation of the polyurethane foams on their properties are presented. The results of studies on thermal stability and mechanical properties of the foams before and after thermal treatment are also reported.

     

Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite Coating

Rigid polyurethane foam (RPUF) has been widely used in many fields, but its high flammability and frequent release of large amounts of toxic smoke during combustion limit its application. Hydrogel coatings, as a kind of environmentally friendly material, contain large amounts of water, which is beneficial to flame retardance of RPUF. MXene, as a two-dimensional inorganic nanomaterial, possesses a large specific surface area and good thermal stability, performing well in smoke suppression and as a physical barrier for flammable gas products and heat. Herein, to address the fire hazards of RPUF, MXene nanosheets were first grafted with double bonds, and then introduced into a polyacrylamide hydrogel system by radical polymerization to prepare MXene-based hydrogel coating (PAAm-MXene). The flame-retardant RPUF (coated RPUF) was prepared by painting the PAAm-MXene coating onto RPUF surface. The dispersion of modified MXene nanosheets (m-MXene) in hydrogels is improved compared with pristine MXene, and the addition of m-MXene contributes to the thermal stability enhancement of PAAm-MXene. Cone calorimetry, water retention test, and open flame combustion test were used to study the flame retardancy, smoke suppression, and water retention of flame-retardant RPUF. The coated RPUF exhibited significant flame retardancy, including reduced peak heat release rate (pHRR) at a maximum by 25.8%, and total heat release rate (THR) at a maximum by 24.6%, and total smoke production at a maximum by 38.9%. The results show that both MXene and m-MXene can improve the flame retardancy, smoke suppression, and water retention of hydrogels, but m-MXene has a better smoke suppression effect than MXene. That can be ascribed to the better dispersion of m-MXene than pristine MXene. The detailed performance improvement mechanisms are proposed. This work will not only improve the flame retardancy of RPUF, but also promotes the exploration of new flame-retardant strategies for RPUF.     

膨胀石墨阻燃蓖麻油磷酸酯聚氨酯保温材料

以蓖麻油和甘油经过酯交换反应生成甘油醇解蓖麻油,然后与双氧水生成环氧醇解蓖麻油,在三苯基膦作催化剂作用下与磷酸二乙酯进行开环反应制备蓖麻油磷酸酯阻燃多元醇。以蓖麻油磷酸酯阻燃多元醇和甘油醇解蓖麻油与膨胀石墨（ＥＧ）和磷酸三乙酯（ＴＥＰ）共混制备了阻燃聚氨酯泡沫,并研究了聚氨酯泡沫的力学性能、阻燃性能和热稳定性。结果表明,蓖麻油磷酸酯阻燃多元醇、ＥＧ提高了聚氨酯泡沫的阻燃性能、热稳定性和力学性能,磷酸二乙酯基团的存在提高了聚氨酯泡沫的阻燃性能,ＥＧ和ＴＥＰ有协同阻燃的作用,使聚氨酯泡沫燃烧时产生更多的炭层,两者共同作用使聚氨酯泡沫的极限氧指数提高到２９．７％。     

Thermal Insulating Rigid Polyurethane Foams with Bio-Polyol from Rapeseed Oil Modified by Phosphorus Additive and Reactive Flame Retardants

In this article, rigid polyurethane foams obtained with the addition of a bio-polyol from rapeseed oil, were modified with the dimethyl propane phosphonate as additive flame retardant and two reactive flame retardants diethyl (hydroxymethyl)phosphonate and diethyl bis-(2-hydroxyethyl)-aminomethylphosphonate. The influence of used flame retardants on the foaming process and characteristic processing times of tested polyurethane systems were determined. The obtained foams were tested in terms of cell structure, physical and mechanical properties, as well as flammability. Modified foams had worse mechanical and thermal insulation properties, caused by lower cellular density and higher anisotropy coefficient in the cross-section parallel to the foam rise direction, compared to unmodified foam. However, the thermal conductivity of all tested foam materials was lower than 25.82 mW/m∙K. The applied modifiers effectively reduced the flammability of rigid polyurethane foams, among others, increasing the oxygen index above 21.4 vol.%, reducing the total heat released by about 41–51% and the rate of heat release by about 2–52%. A correlation between the limiting oxygen index values and both total heat released parameters from the pyrolysis combustion flow calorimetry and cone calorimetry was observed. The correlation was also visible between the value of the heat release capacity (HRC) parameter obtained from the pyrolysis combustion flow calorimetry and the maximum average rate of heat emission (MARHE) from the cone calorimeter test.     

天然植物原料改性聚氨酯及其应用

综述了含天然纤维素的植物原料在聚乙二醇和聚酯多元醇中进行液化及制备改性聚氨酯(PU)。介绍了植物纤维改性PU、玉米秸杆改性PU、稻草改性PU、甘蔗渣改性PU、树皮改性PU的性能及应用。重点介绍了树皮的主要成分单宁改性淀粉PU的耐水性、抗菌性和热稳定性。这些植物原料通过液化改性可替代部分石油多元醇,以满足性能各异的高附加值聚氨酯的要求及在卫生、家具、食品包装和保温隔热等领域中的应用。     

聚氨酯硬泡改性研究的新进展

综述了颗粒填充、纤维增强、多孔无机材料增强、原料替代等聚氨酯硬泡改性研究的最新进展,介绍了聚氨酯硬泡改性的发展趋势。