木质素酚醛树脂基泡沫炭的制备及其油水分离性能（英文）

采用绿色处理过程从草本植物中提取14 wt%木质素,以该木质素取代25%苯酚制备酚醛树脂,并以木质素酚醛树脂为碳源、聚氨酯泡沫为模板制备泡沫炭,并研究其油水分离性能。结果表明,所得泡沫炭具有开放大孔、低密度、疏水亲油的性能,并对有机溶剂和油品展现出良好的吸附性能,其饱和吸附量可达其自身重量的12~41倍。泡沫炭吸附有机溶剂后可通过直接燃烧进行脱附,循环使用10次后,泡沫炭对植物油仍可保留83%的饱和吸附量。     

制备莫来石泡沫陶瓷的工艺因素

采用红柱石和a—Al2O3为原料,以聚苯乙烯粒子（EPS）为造孔剂,通过烧结法制备莫来石泡沫陶瓷。借助XRD和SEM分析获得莫来石相的组成和形貌,通过正交试验,探讨了粘结剂加入量、造孔剂粒度及球磨时间等工艺参数对泡沫陶瓷结构和性能的影响,在此基础上进一步讨论造孔剂加入量对密度和强度的影响。结果表明：粘结剂加入量对密度和强度的影响较大,造孔剂粒度次之,球磨时间影响最小。1450℃烧结,红柱石和氧化铝按质量比80：20,EPS粒径小于0．60mm、加入9wt％造孔,可以制备性能优良的莫来石泡沫陶瓷,其表观密度0．52g／cm3,孔隙率为83％,抗折强度1．54MPa。     

PANI多孔吸附剂对酸性红G循环吸附应用探究

采用原位化学氧化聚合法制备了聚苯胺（PANI）/聚氨酯类填料（PBG）复合材料并对其形貌和结构进行了表征，探究不同条件下PANI/PBG复合材料对酸性红G（ARG）的吸附性能与吸附机理以及该吸附剂的再生性能。研究结果表明，（1）PANI/PBG复合材料吸附ARG的最佳投加量为8 g/L,在pH=1～5时，吸附去除率在90%以上；（2）PANI/PBG的平衡吸附量可达228.50 mg-ARG/g-PANI,且吸附平衡时间仅需30 min;（3）PANI/PBG复合材料吸附ARG过程符合准二级动力学模型和Langmuir等温线模型，表明该吸附过程为单层化学吸附，拟合的最大吸附量Q_m为368.59 mg/g;经过6次再生循环后PANI/PBG复合材料仍有良好的吸附性能。     

SiCp增强泡沫铝制备工艺研究

对熔体发泡法制备SiCp增强泡沫铝基复合材料的制备工艺进行了探索，通过正交试验研究了SiC的粒度、发泡剂TiH2的加入量、发泡温度、保温时间等工艺参数对泡沫铝孔隙率及孔结构的影响，确定了制备SiCp增强泡沫铝基复合材料的最佳工艺参数：掺入10％（质量分数）1000目的SiC颗粒增粘，在发泡剂TiH2加入量为2％（质量分数），搅拌时间2min，保温温度700℃以及保温时间3min的工艺条件下，制得的泡沫铝的孔隙率达到80％，平均密度达到了0．5g／cm^3，且基本没有无泡层。最后对泡沫铝的产业化生产的可行性作了讨论。     

迷宫形开孔硬质聚氨酯泡沫制备和性能研究

以多亚甲基多苯基异氰酸酯(PM-200)、聚醚多元醇(5110)为主要原料,以硅油(L580)为稳泡剂,水(H2O)为发泡剂,采用一步发泡法制备一系列不同密度硬质聚氨酯泡沫材料,通过水压穿孔工艺实现硬质聚氨酯泡沫开孔,制备具有形如迷宫样的相互贯通的开孔硬质聚氨酯泡沫。研究了泡沫密度和开孔压力对泡沫开孔率和压缩强度的影响,以及开孔率对吸声系数的影响。结果表明:开孔压力越大,相应的开孔率越大;在开孔压力相同的情况下,泡沫的密度越小,开孔率越大;开孔率越大,材料吸声系数越大;开孔压力的变化对泡沫压缩强度影响不大。     

碱式硼酸镁改性聚氨酯泡沫阻燃特性研究

为了研究碱式硼酸镁改性聚氨酯泡沫的阻燃性能,该文先采用水发泡“一步法”制作多种含量碱式硼酸镁改性聚氨酯泡沫,再采用锥形量热（CONE）和极限氧指数（LOI）方法对制备所得的聚氨酯泡沫材料的阻燃性能进行表征。试验结果表明,当添加整体质量为1%的碱式硼酸镁时,其LOI由17.2提升至17.8;当添加整体质量为10%的碱式硼酸镁时,其LOI上升至24.1。此外,随着增加碱式硼酸镁的添量,可以有效降低聚氨酯泡沫的热释放速率峰值和总热释放量,添加10%碱式硼酸镁改性的聚氨酯泡沫的阻燃效果最好。目前的工作对今后聚氨酯泡沫阻燃改性的研究具有参考意义。     

聚氨酯泡沫铝复合材料动态力学实验

通过在开孔泡沫铝中填充聚氨酯得到了聚氨酯泡沫铝, 利用Hopkinson杆对泡沫铝与泡沫聚氨酯组成的三维连续网络增强复合材料进行了在不同相对密度、 应变率和聚氨酯含量下的动态压缩实验。结果表明, 在相同应变率和相对密度下, 与泡沫纯铝相比, 聚氨酯泡沫铝屈服强度和压缩应变量显著增加, 而且应力-应变曲线出现明显的抖动。 随着应变的不断增大, 应力也逐渐增加, 在达到某一相同的应变时, 聚氨酯泡沫铝的应力值较高, 吸能量也较多。另外, 当应变率增加时, 聚氨酯泡沫铝表现出很明显的应变率效应。      

啶虫脒在超高交联吸附树脂上的吸附及脱附性能研究

本文从动态和静态的角度研究了均苯四甲酸酐修饰的超高交联吸附树脂（PMAR）和1,2,4-苯三酸酐修饰的超高交联吸附树脂（TMAR）对啶虫脒的吸附和脱附行为。结果表明：两种树脂对啶虫眯的吸附和脱附效果都比较好,TMAR的静态吸附量为470．9mg·g^-1干树脂,饱和吸附量为562．7mg·g^-1干树脂;PMAR的静态吸附量为453．4mg·g^-1干树脂,饱和吸附量为559．1mg·g^-1干树脂。两种树脂都易于脱附,用2mol·L^-1 HCl：乙醇（体积比1：1）作脱附剂,温度323K,脱附剂体积为9．5BV（床体积）时,PMAR的脱附率为98．13％,TMAR的脱附率为99．83％。     

碳纳米纤维气凝胶的制备及其吸油性能

先用静电纺丝-液相接收技术制备蓬松的聚丙烯腈(PAN)三维纳米纤维，然后将其进行热稳定化处理得到超轻纳米纤维气凝胶(CNFAs)。CNFAs内部是碳纳米纤维交叠形成的开孔网络，发生80%应变后能回弹到原形。用聚二甲基硅氧烷(PDMS)气相沉积疏水化处理后，CNFAs的水接触角增大到145°。研究了静电纺丝纳米纤维的原始堆积密度对CNFAs的体积收缩率、密度、吸油容量以及循环吸附量的影响，结果表明：这种气凝胶的机械性能优异。纳米纤维合适的初始堆积密度为4 mg·mL^-1，制备出的CNFAs对油类污染物的吸附量可达到自重的185倍；用燃烧和挤压方法10次循环回收吸附饱和的CNFAs，其吸附容量仍保持稳定。     

轻质客车地板结构优化设计及验证分析

针对现有客车地板密度较大的现状,本文以聚氨酯泡沫为芯材,通过对其结构进行设计和优化,开发了一种新型泡沫塑料轻质客车地板。将PU泡沫密度控制在450 kg/m3,增强面层为400 g/m2的玻璃纤维布增强微发泡聚氨酯,地板的握螺钉力可达1 080 N。     

Structure–property relationships in polyurethanes derived from soybean oil

Two types of soy polyols have been prepared, one with secondary OH groups resulted from epoxidation of soybean oil followed by methanolysis (polyol type I) and the other with primary OH groups created from hydroformylation of soybean oil followed by hydrogenation (polyol type II). Cast polyurethane resins were prepared from these two types of polyols with Isonate 2143L, and rigid polyurethane foams were prepared from a blend of soy polyol and glycerol with PAPI 2901. Polyol II is much more reactive than polyol I towards polyurethane formation. This is evidenced from studies on polyurethane gel-times, glass transitions and rigid foam mechanical strengths. The reaction for the polyurethane formation is more complete for polyol II resulted from its higher reactivity than polyol I, although a less rigid polyurethane material is resulted from polyol II than from polyol I. Polyol type II also requires lower amounts of catalysts for rigid foam formulation. Both rigid foam systems produce foams having the required mechanical strength. The polyol II foam system behaves much like conventional rigid foam systems where the strength are proportional to system OH content, while the less reactive polyol I system does not.     

Semi-rigid biopolyurethane foams based on palm-oil polyol and reinforced with cellulose nanocrystals

In this study, water-blown biopolyurethane (BPU) foams based on palm oil were developed and cellulose nanocrystals (CNC) were incorporated to improve the mechanical properties of the foams. In addition, the foams were compared with petroleum polyurethane (PPU) foam. The foam properties and cellular morphology were characterized. The obtained results revealed that a low-density, semi-rigid BPU foam was prepared using a new formulation. CNC as an additive significantly improved the compressive strength from 54 to 117 kPa. Additionally, cyclic compression tests indicated that the addition of CNC increased the rigidity, leading to decreased deformation resilience. The dimensional stability of BPU foams was increased with increasing CNC concentration for both heating and freezing conditions.Therefore, the developed BPU nanocomposite foams are expected to have great potential as core material in composite sandwich panels as well as in other construction materials.     

聚氨酯/环氧树脂互穿网络半硬泡沫的力学性能及吸能特性

采用同步法制备了聚氨酯/环氧树脂互穿聚合物网络(IPN)半硬泡沫。通过压缩和拉伸试验研究了泡沫材料密度对力学性能的影响。研究表明,在所研究的密度范围内,泡沫的压缩模量和屈服强度均与密度成指数关系。泡沫的拉伸模量和断裂强度与密度也存在类似的关系。利用这些方程可以很好地预测泡沫力学性能随密度的变化关系。IPN泡沫兼有较好的韧性和较高的拉伸强度。相同形变下,相同密度IPN半硬泡沫拉伸过程的单位体积吸能大于压缩过程的单位体积吸能。     

Piezoresistive and compression resistance relaxation behavior of water blown carbon nanotube/polyurethane composite foam

The in-situ bulk polycondensation process in combination with a ball milling dispersion process was used to prepare the water blown multiwall carbon nanotubes (CNT)/polyurethane (PU) composite foam. The mechanical properties, piezoresistive properties, strain sensitivity, stress and resistance relaxation behaviors of the composite foams were investigated. The results show that the CNT/PU composite foam has a better compression strength than the unfilled polyurethane foams and a negative pressure coefficient behavior under uniaxial compression. The resistance response of CNT/PU nanocomposites foam under cyclic compressive loading was quite stable. The nanocomposite foam containing a weight fraction of carbon nanotubes close to the percolation threshold presents the largest strain sensitivity for the resistance. The characteristic of resistance relaxation of CNT/PU composite foam is different from the stress relaxation due to the different relaxation mechanism. During compressive stress relaxation, the CNT/PU foam composites have excellent resistance recoverability while poor stress recoverability.     

Modeling the mode I fracture toughness of anisotropic low-density rigid PUR and PIR foams

Low-density foams have to possess a sufficient resistance to cracking in order to ensure the mechanical integrity of foam materials in service, even when not intended for load-bearing applications. In this study, mode I fracture toughness in the foam rise direction has been experimentally characterized for anisotropic rigid commercial polyurethane foams as well as for polyisocyanurate foams produced using polyols derived from rapeseed oil and filled with a montmorillonite nanoclay. Rectangular parallelepiped unit-cell based scaling relations expressing foam toughness via its relative density, cell dimensions, geometrical anisotropy, and the ultimate tensile stress of the base polymer have been employed for prediction of foam toughness. Assuming a brittle fracture of foam struts, a conservative estimate of toughness is obtained. It is demonstrated that considering the yielding of foam struts at the crack front as the criterion of crack extension provides a closer estimate of foam toughness.     

MWNT reinforced polyurethane foam: Processing, characterization and modelling of mechanical properties

The mechanical properties of a foam material changes when the foam is reinforced with nanoparticles. In this paper it is investigated how the addition of multi-walled carbon nanotubes (MWNTs) influences the effective properties of polyurethane foam. Both pure and nano-reinforced foams containing different amounts of MWNT are produced and both pristine and functionalized MWNT are used as reinforcement. The MWNT are dispersed in the polyol using high-shear mixing with various mixing times to examine how that influences the properties of the produced foams. SEM is used to characterize the microstructure of the produced foams and these examinations reveals that the foam changes from a completely closed cell material for the pure PU foam to a partly open celled foam when adding MWNT. Compressive tests are performed in order to determine the strength and stiffness of the produced foams and the increase in these properties are very dependent on both the wt.% of MWNT and the mixing time used to disperse them in the polyol. Furthermore, the effective properties of the reinforced foams are determined using the Mori-Tanaka (MT) method and generally the correlation between the experimentally and numerically determined properties improves when the mixing time used increases for a constant wt.% of MWNT.     

Development of rigid bio-based polyurethane foam reinforced with nanoclay

Integration of organic nanoclay into bio-based polyurethane (PU) foam is a promising alternative to enhance the foam’s properties via green technology. In this paper, modified diaminopropane montmorillonite (DAP-MMT) nanoclay was introduced into palm oil-based PU foam at different weight loadings, namely, 0, 2, 4, 6, 8, and 10 wt.%, in order to investigate the effects on the mechanical and thermal properties of the foam. Several tests and characterizations were carried out to study the surface morphology, density, compressive strength and thermal stability of the foam. It was found that foam exhibited an exfoliated or intercalated microstructure based on the DAP-MMT contents. The X-ray diffraction analysis showed that below 4 wt.%, the foams displayed exfoliated structures while beyond the value, the foams exhibited the intercalated morphologies. Closed cells with different cell sizes were observed when the DAP-MMT contents were varied. Meanwhile, thermal stability and compressive strength of foams increased with increasing DAP-MMT contents up to 4 wt.%, as shown by thermogravimetry analysis and compression test, respectively.     

一步法制备聚氨酯/碳纳米管复合泡沫材料及其性能

采用球磨法将碳纳米管分散到聚醚三元醇中,以水为发泡剂,采用一步法原位聚合制备了聚氨酯(PU)/碳纳米管(CNTs)复合泡沫材料,研究了发泡剂水的添加量和碳纳米管的含量对复合材料密度和性能的影响.结果表明,随水添加量的增加,泡沫材料的密度、压缩模量、拉伸模量以及断裂伸长率呈下降的趋势;碳纳米管的加入大幅度提高了材料的压缩...     

Stiffness and energy dissipation in polyurethane auxetic foams

Auxetic open cell polyurethane (PU) foams have been manufactured and mechanically characterised under cyclic tensile loading. The classical manufacturing process for auxetic PU foams involves multiaxial compression of the conventional parent foam, and heating of the compressed specimens above the T_m of the foam polymer. Eighty cylindrical specimens were fabricated using manufacturing routes modified from those in the open literature, with different temperatures (135 °C, 150 °C), compression ratios and different cooling methods (water or room temperature exposure). Compressive tensile cyclic loading has been applied to measure tangent modulus, Poisson’s ratios and energy dissipated per unit volume. The results are used to obtain relations between manufacturing parameters, mechanical and hysteresis properties of the foams. Compression, both radial and axial, was found to be the most significant manufacturing parameter for the auxetic foams in this work.     

A visco-hyperelastic constitutive description of elastomeric foam

This study focuses on the constitutive modelling of finite deformation in elastomeric polyurethane foams—in particular, PORON-4701-59-25045-1648 (0.4 g/cm³ density) and PORON-4701-59-20093-1648 (0.32 g/cm³ density). Their mechanical properties under compression, for engineering strains up to about 80%, are characterized over a range of strain rates between 10⁻² and 10³/s. Dynamic compression is applied using a split Hopkinson pressure bar device. Experimental results show that the behaviour of elastomeric foam is sensitive to strain rate and can be described by a visco-hyperelastic material model. In this model, the quasi-static response is defined by compressible hyperelasticity, whereby the strain energy potential is assumed to be representable by a newly proposed polynomial series with three independent parameters. Strain rate sensitivity is characterized by incorporating a nonlinear Maxwell relaxation model with four parameters. The (seven) material parameters in the constitutive model are determined from high-speed mechanical testing methods tailored for high-compliance materials. A comparison of predictions based on the proposed frame-independent constitutive equation with experiments shows that the model is able to describe the rate dependent behaviour of the elastomeric foams examined.