竹单板/泡沫铝复合材料的制备及胶合性能评估

Preparation and bonding performance evaluation of bamboo veneer/foam aluminum composites

近年来,铝基泡沫材料在汽车、航空航天领域表现出较好的应用潜力,但铝基泡沫材料抗弯强度和刚度方面性能较差,且价格昂贵,限制了其在建筑、高铁车厢板及场馆装潢等方面的使用。鉴于此,选用价格低廉、保温美观的竹单板作为面层材料,轻质低密度的泡沫铝作为芯层材料,并对其进行合理组坯及热压,得到自然美观、轻质高强的新型结构材料,从而使其广泛应用于建筑、家具、地板等基材中。以竹单板(横拼)和闭孔泡沫铝为原料,采用3组不同施胶量的卡夫特AB胶、环氧树脂AB胶和酚醛树脂胶3种胶黏剂对竹单板与泡沫铝的界面进行胶接,制备竹单板/泡沫铝夹芯复合材料,探究了不同类型的胶黏剂及施胶量对复合材料力学性能、吸水性能及界面胶合机理的影响。结果分析表明:选用施胶量为340 g/m^(2)的水溶性酚醛树脂作为胶黏剂所制备的复合材料,其静曲强度、弹性模量及胶合强度均达到最大值,24 h吸水厚度膨胀率和72 h吸水率达到最小值,且竹单板和泡沫铝通过胶黏剂使得界面紧密黏合。试验证明使用施胶量为340 g/m^(2)的酚醛树脂胶接得到的材料各项综合性能最优,有利于工业化生产和实际推广利用。

In recent years,aluminum-based foam materials have been rapidly developed and potentially applied in automotive and aerospace fields.However,aluminum-based foam materials have poor performance in bending strength and stiffness,as well as high cost,which limit their applications in construction,high speed rail car floor,and entertainment venues.In view of this,the low cost and beautiful insulation bamboo veneer are used as the surface materials,and the light weight and low density foam aluminums are used as the core materials.A new type of structural material with natural beauty,light weight,and high strength was obtained by the reasonable billet assembly and hot-pressing technology.It can be widely used in furniture,flooring and other substrates.In this study,the bamboo veneers and foam aluminums are used as raw materials,and three kinds of adhesives,i.e.,the kraftAB,epoxy resin and phenol-formaldehyde resin,are used to prepare bamboo veneer/foam aluminum composites.The effects of different types of adhesives and sizing amount on the mechanical properties,water absorption properties and interface bonding mechanism of composites were investigated.The results showed that the static bending strength,elastic modulus,and bonding strength of the composites with 340 g/m^(2) water-soluble phenol-formaldehyde resin as adhesive,reached the maximum value.The 24 h thickness expansion rate of the water absorbing and the 72 h water absorption were reached the lowest value.Adhesives made the interface between bamboo veneer and aluminum foam to be tightly bonded.It was proved that the composites bonded by the phenol-formaldehyde resin with a sizing amount of 340 g/m^(2) had the best overall performance,which was conducive to the industrial production and promotion.In addition,bamboo veneer/foam aluminum composites can also be used as sound-absorbing and sound insulation materials and electromagnetic shielding materials in the fields of motor car floor,partition board,and lightweight building decoration.At present,there are limited researches on bamboo veneer/foam aluminum composites.The next step of our research group is to further study its sound absorption performance and electromagnetic shielding effectiveness.