| According to the new idea of hollow fiber damping composite materials made by better damping polymer, the technology parameters and performance evaluation of preparating hollow fiber damping materials with acrylic rubber(ACM) were explored.And the inner relation between the structure design and its performance or damping mechanism was studied.And the modulation mechanism of obviously improving its structure damping was discussed. Through a lot of experiments, the damping modulation mechanism and its law of the hollow fiber damping composite have been obtained. This study has important academic significance to realize the integration of multiple damping complex function for developing new damping materials and to explore its damping modulation mechanism. In order to meet the increasing development demand of structure damping composite with high damping, lightweight and function integration,this research may laid the foundation of theoretical and experimental research on developing new type high-rise building partition wall materials and aerospace damping composite with high damping and light quality for reduction of their vibration and noise.The acrylic rubber is known to have excellent heat-, oil-, ozone-,anti-cracking and weather resistance, which have broad application prospects in the aerospace, civil aviation and maritime fields. But the damping properties of the acrylic rubber is dominated by the glass transition, usually, the glass transition temperature around which the useful damping temperature range is narrow is relatively low. Therefore, in order to obtain a broader damping property, a modification of ACM is needed.Hollow fiber is a kind of tubular chemical fiber with a good cushion performance, and polyvinyl chloride(PVC) is polar and has a high glass transition temperature, mechanical strength, small viscosity and the solubility parameters near to ACM. Therefore, blending ACM with PVC, not only improves its glass transition temperature and broadens the damping temperature range, but also reduces the viscosity to make it easier spun. So this study is to use the method of solution blending which blends ACM with PVC to produce the ACM/PVC hollow fiber damping materials by spinning technology. This paper mainly carries out the following respects of content:First of all, the compatibility of the blends is investigated. The ACM/PVC blend system is compatible in the blend ratio of50:50～70:30, which is tested by the solvent analysis, means of DMA and FTIR. And the cross-section structure of ACM/PVC hollow fiber by scanning electron microscopy(SEM) is similar to that used in water treatment, while the distinctions in the internal or external morphology due to the differences between materials.Secondly, the influence of polymer concentration, blending ratio and extrusion rate on mechanical properties and dynamic mechanical properties of the ACM/PVC hollow fiber are discussed by many experiments, the optimum blending ratio and the suitable polymer concentration are obtained, and ACM/PVC hollow fiber is contrasted with NBR/PVC. The results show that, within experimental conditions range, the optimum ingredient is22wt%of polymer concentration and blending ratio50:50with the condition of that, the tensile properties and damping properties of ACM/PVC hollow fiber are the best, which damping loss factor can reach0.9. The tensile strength increases with increases in polymer concentration and extrusion rate and decreases with the reduction of blending ratio. DMA measurements revealed that the damping property of the hollow fiber structure is superior to that of the plate membrane with the same material under the same conditions, and for the same diameter hollow fiber, specimen shape has no effect on the damping loss factor, but changing the size of inner diameter, the loss tangent(tanδ) will change. In addition, it is observed that the ACM/PVC blend shows not only a single tanδ peak and the position of peak of the glass transition temperature shift to a higher temperature with the increase of PVC content, but also its temperature range of tanδ>0.3is40-65℃, resulting in that ACM/PVC mixture is a promising damping-material, and comparing to NBR/PVC hollow fiber, the tensile strength, the tanδ and the glass transition temperature of ACM/PVC mixture is better.Finally, adding hindered phenol(AO-60), nano-TiO2, nitrile rubber(NBR) to ACM/PVC blends are studied. The results show that nano-TiO2mixed to ACM/PVC mixture can lessen the viscosity of casting solution and make spinning easier. What’s more, it improves the tensile properties and makes the position of peak shift to a higher temperature, but reduces the height of the tanδ peak. Whereas there is an opposite conclusion with the addition of AO-60that increases the viscosity and lower tensile performance, but the same to the damping performance. Adding AO-60doesn’t improve the tanδ of ACM/PVC blends by now the hollow fiber preparation technology, which shows that performance exhibited depends on preparation technology. |
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