头盔衬垫用聚氨酯泡沫塑料的制备与性能研究

介绍聚氨酯（PUR）泡沫塑料的制备原理,对硬质PUR泡沫塑料、半硬质PUR泡沫塑料和聚苯乙烯（PS）泡沫塑料的力学性能及其在不同环境条件下的性能变化进行对比分析,并对成型出的硬质和半硬质PUR泡沫塑料衬垫进行穿透和碰撞试验。结果表明,硬质PUR泡沫塑料的韧性较PS泡沫塑料高,强度较PS泡沫塑料低,但随着密度的增大,硬质PUR泡沫塑料的力学性能与PS泡沫塑料的差距减小;PUR泡沫塑料的耐环境性优于PS泡沫塑料;硬质和半硬质PUR泡沫塑料衬垫的抗穿透性能和碰撞性能满足GJB1564—1992的技术要求,PUR泡沫塑料可以取代PS泡沫塑料用于飞行员头盔衬垫。     

含有短切导电纤维聚氨酯泡沫塑料的吸波性能研究

通过对一种含导电短纤维的聚氨酯(PUR)泡沫塑料吸波性能的研究,探讨了纤维吸收剂的电导率、含量和泡沫塑料试样厚度对PUR泡沫塑料吸波性能的影响。结果表明,在一定范围内,纤维电导率增大可使PUR泡沫塑料对电磁波的损耗增加;纤维含量增大可增加其谐振子数目,有利于衰减电磁波;试样厚度增加可使PUR泡沫塑料吸波性能增强,在Ka波段尤为明显。     

我国聚氨酯泡沫塑料的发展近况

详细阐述我国近几年聚氨酯(PUR)泡沫塑料的生产情况,对企业生产规模、生产技术及产品种类均进行了探讨,并对PUR泡沫塑料的市场需求情况及各行业所用泡沫塑料比例进行了分析;同时还详尽地介绍了目前我国PUR泡沫塑料的技术进展,系统说明了发泡剂应用研究在当前的重要性和紧迫性;指出了今后PUR泡沫塑料的发展方向。     

硬质聚氨酯泡沫塑料在屋面保温防水工程中的应用

论述在建筑工程的屋面保温防水工程中广泛应用的硬质聚氨酯(PUR)泡沫塑料的优点,包括优良的隔热保温性能、独特的抗水渗透性能,以及质轻、力学性能高、抗侵蚀、耐老化等。介绍了硬质PUR泡沫塑料在屋面保温防水工程中的施工要点及喷涂时的注意事项。并指明了硬质PUR泡沫塑料应用在屋面保温防水工程中产生的经济效益。     

稻秸秆/玉米淀粉胶复合材料的制备及性能

以玉米淀粉为原料,H2O2为氧化剂,制得氧化玉米淀粉胶。利用模压方法制备了稻秸秆/玉米淀粉胶复合材料,基于正交试验方法,研究了原料配比对复合材料的密度、抗压强度、吸湿性及可降解性能的影响。结果表明:稻秸秆/玉米淀粉胶复合材料密度随稻秸秆含量增加,先升高后降低;当稻秸秆含量为16.3%时,复合材料密度最小;随玉米淀粉胶含量增加复合材料抗压性能降低。当稻秸秆∶改性淀粉∶玉米淀粉胶∶滑石粉∶碳酸氢氨的质量比为6∶9∶15∶5∶1时,复合材料抗压强度较高。稻秸秆/玉米淀粉胶复合材料在潮湿环境下的降解性能良好,但与聚苯乙烯泡沫塑料相比易吸潮。     

秸秆焦油基聚醚多元醇的合成及其在PUR泡沫中的应用

采用气/质联用仪对秸秆焦油的成分进行了分析,确定了49种化合物,相对酚总量为66.23%。用秸秆焦油、多聚甲醛、二乙醇胺、环氧丙烷为原料,制备焦油基Mannich聚醚多元醇(TMP),对反应过程进行了探索,并用TMP、二异氰酸酯系化合物(粗MDI)等制备了焦油基聚氨酯(PUR)泡沫。结果表明,合成焦油基Mannich碱的较佳条件为反应温度80℃,反应时间3 h,二乙醇胺的转化率可达到90.47%。研究了环氧丙烷的添加量对TMP及其PUR泡沫结构与性能的影响,并将TMP基PUR与纯苯酚(PMP)基PUR进行了性能比较。结果表明,TMP基PUR泡沫具有PMP基PUR泡沫相近的力学性能和热稳定性,且成本较低,因此具有良好的应用前景。     

PIR与PUR泡沫塑料性能对比研究

在相同的实验条件下分别制备了硬质聚异氰脲酸酯泡沫(PIR)和普通硬质聚氨酯泡沫塑料(PUR),对比研究了PIR和PUR的部分性能指标。利用场发射电子扫描显微镜(SEM)对泡沫的形貌进行了表征和对比;利用热失重分析仪对泡沫的耐温性进行了对比分析,同时研究了PIR和PUR的力学强度和不同阻燃剂添加量对泡沫氧指数的影响。结果表明,PIR与PUR相比,泡沫保持了较高的闭孔结构,PIR的耐温性明显高于PUR,泡沫的力学强度和阻燃性能都得到了较大的提高。     

高速铁路用聚氨酯填充材料快速试验方法的研究

针对采用聚氨酯(PUR)作高速铁路填充材料时,现场施工条件下不可能在PUR固化过程中进行加热及室温PUR固化周期长的缺点,探讨实验室可用的快速试验方法。先用差示扫描量热分析和红外光谱分析确定后处理温度,再根据实际情况确定后处理时间,并与未后处理的试样进行性能对比。结果表明,用该方法研究高速铁路用PUR填充材料可大大缩短试验周期。     

耐热PUR—PIR泡沫塑料的研究

试图用聚氨酯(PUR)来改性聚异氰脲酸酯(PIR),以降低脆性,并保持耐热性,从而达到工业上使用的目的。为此,重点对5种催化剂进行了单独和复合的活性试验及评选;对原料、工艺配方、不同异氰酸酯指数与PUR-PIR泡沫塑料热学性能的关系等进行了研究。试验结果表明,通过PUR改性,PIR泡沫塑料的耐热温度(即工作使用温度)可达160℃或160℃以上,滚动脆性损失最大不超过29％,为工业应用指出了一条切实可行的途径。     

增强PUR-R泡沫塑料力学性能的测试和讨论

对硬质聚氨酯（PUR－R）泡沫塑料（纯的和增强的）进行了多种力学性能的测试和讨论，给出了实验结果和实用的关系式。纯PUR－R泡沫塑料的力学性能随密度的增大而显著提高；添加增强材料短切玻璃纤维和玻璃微珠可有效地提高PUR－R泡沫塑料的力学性能，综合来看，短切玻璃纤维增强效果不如玻璃微珠，质量分数为10％的玻璃微珠增强效果最好。     

Recycling of rigid polyurethane foam: Micro-milled powder used as active filler in polyurethane adhesives

Rigid polyurethane (PUR) foams are widely used as heat insulation material in construction industry or for electronic appliances manufacturing. After finishing their life-time, it is necessary to eliminate foam wastes. The aim of this study was to prepare a pair of industrial PUR adhesives of medium viscosity containing recycled rigid PUR foam. Three methods of milling were tested: knife-milling, two-roll milling, and ball-milling. Only two-roll milling gives the PUR micro-powder usable for following adhesives modification. The micro-powder was used as passive filler in PUR adhesives and potential reactivity for polyol pack replacement was studied. Hydroxyl and amine numbers were determined in mixture with virgin polyol. One-component PUR prepolymer adhesive was prepared using various dosages of the micro powder and the tensile strength of bound wood was measured. As additional parameters, also free film adhesive mechanical parameters were tested and particle size distribution of the micro powder was analyzed. Two adhesive formulations were prepared for independent evaluation of the micro powder reactivity. The results showed growing of the mechanical strength of wood bonding with growing dosage of the micro powder.     

CFD‐Simulation der Feststoffeinbindung in einen Sprühstrahl

Sound‐absorbing mats consisting of cross‐linked Polyurethane (PUR) foam and metal reinforcements, door panels and centre consoles for the interior of vehicles became important products for automotive component suppliers. The leading technology for the production of foam on the base of PUR with noise absorbing properties is the application of powder insertion (e.g. metal) in the PUR spray. The numerical simulation (CFD) of the spray including the particle‐droplet interaction is presented. The theoretical background of the implemented models is explained and the experimental results achieved with a pilot plant are compared with the numerical results. The presented simulation offers the possibility to suitably predict the metal powder distribution in a PUR spray.     

混杂增强聚氨酯复合硬质泡沫塑料的研制

系统介绍混杂增强聚氨酯复合硬质泡沫塑料的制备情况，详细分析聚氨酯硬质泡沫塑料制备过程中的工艺问题，表征与分析其结构与性能，着重分析偶联剂对填充物增强性能的影响以及填充物含量对聚氨酯硬质泡沫塑料吸水性能的影响，介绍聚氨酯硬质泡沫塑料的应用，最后指出其发展前景。     

Effects of liquid‐type silane additives and organoclay on the morphology and thermal conductivity of rigid polyisocyanurate‐polyurethane foams

This article investigates the effects of liquid‐type silane additives and organoclay as a solid‐type additive on the morphological, mechanical and thermal insulating properties of polyisocyanurate‐polyurethane (PIR‐PUR) foams. The organoclay likely acted as nucleating agents during the formation of PIR‐PUR foams. When the liquid silane additives and organoclay were added, the cell size and thermal conductivity of the PIR‐PUR foams appeared to be decreased. However, organoclay did not contribute to reduce the cell size distribution of the foam. PIR‐PUR foams synthesized with tetramethylsilane as a liquid‐type additive showed a smaller average cell size and lower thermal conductivity than that of PIR‐PUR foams synthesized with the other silane additives or with organoclay as a solid‐type additive. For the PIR‐PUR foam with organoclay/TEMS (1.5/1.5 php) mixture, cell size and thermal conductivity of the foam showed similar to the foam with TEMS. These results suggest that smaller cell size appears to be one of the major factors in the improvement of thermal insulation properties of the PIR‐PUR foams. Silane additives did not seem to have a strong effect on the flammability of the PIR‐PUR foams. However, heat resistance was more dominant for the foam with the organoclay at the higher temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

汽爆秸秆对磷矿粉溶解作用及其溶解残渣对小麦生长的影响

为探究生物质对磷矿粉的溶解作用,以玉米秸秆为原料,利用蒸汽爆破（汽爆）技术释放有机酸,在高温水热条件下溶解磷矿粉并制备含磷腐殖酸。通过实验对汽爆秸秆溶解磷矿粉工艺进行了探究及优化,并利用傅里叶红外光谱（FT-IR）、扫描电子显微镜（SEM）和X射线荧光光谱（XRF）进行分析和表征。研究结果表明：15 g汽爆秸秆与1 g磷矿粉以及75 mL水在170℃、加入10% CaCl₂的条件下,反应3 h的溶磷量为1.46 mg/g（以秸秆质量计,下同）。加入与磷矿粉相同质量的NaHSO₄后可使体系pH值降低至2,pH值的降低是磷溶出的关键因素,溶磷量提高为13.10 mg/g。溶磷后的秸秆制备腐殖酸作为小麦盆栽肥料,用量0.2%时,小麦株高、根长、叶绿素含量和相对电导率均显著高于空白组。     

短纤维增强HDPE泡沫复合材料的研究

报道了以尼龙－６短纤维增强ＨＤＰＥ结构泡沫材料以及木粉填充ＨＤＰＥ结构泡沫材料的力学性能，探讨了粘合剂对尼龙－６短纤维和ＨＤＰＥ泡沫基材的粘合使用，并分析了不同加工助剂对木粉填充ＨＤＰＥ发泡体系加工性能和外观的影响。     

玉米秸秆粉料在放电等离子体中的裂解反应

为了实现在无氧化、无燃烧的情况下玉米秸秆粉料一步分解为糖产物,开展了高气压放电等离子体处理秸秆粉料的实验研究。结果发现,玉米秸秆粉料在不经复杂的预处理和添加助剂情况下,可一步裂解为糖产物,得到了单糖、二糖等产物。通过对秸秆及秸秆主要成分纤维素、半纤维素和木质素反应产物的分析与表征,得到了较好的裂解条件,在环境温度70℃、压力90 kPa、N₂媒质气体流量0.35 L•min^-1和常压饱和水蒸气流量0.1 L•min^-1、放电电压3 kV、放电间隙0.60 mm的条件下,放电60 min后玉米秸秆粉料转化率为69.36%,糖选择性为39.68％,糖产率为40.16％。这些结果初步显示了玉米秸秆在无酸碱、无高温高压、无需复杂预处理的条件下分解成糖的可能性。     

泡沫塑料研究进展

从传统泡沫塑料改性和新型泡沫塑料研究两个方面综述目前泡沫塑料高性能化的主要途径和研究方法,着重介绍聚氨酯、聚氯乙烯泡沫塑料等的改性方法及聚酰亚胺、聚甲基丙烯酰亚胺泡沫塑料等新型泡沫塑料的研究进展,并展望了泡沫塑料未来的应用前景和发展趋势。