间歇注气法提高微发泡注塑产品表面质量的研究

Study on Surface Quality Improvement of Microcellular Foaming Injection Molding Product by Intermittent Gas Injection

采用间歇注气法制备了聚丙烯(PP)微发泡注塑产品,利用原子力显微镜对样品的表面形态进行了观测,扫描电子显微镜对泡孔形态进行检测,并对其表面粗糙度进行计算。研究了塑化长度和注气延时对微发泡注塑产品表面质量的影响。结果表明,在塑化长度不变的情况下,随着注气延时的增加,制品的质量降低,流动前沿所含超临界气体体积减少,表面质量因此而提高。在注气延时不变的情况下,随着塑化长度的增加,不含泡孔的制品表层厚度也加大。

Polypropylene （PP） microcellular injection molding products were prepared by intermittent gas injection method. The surface morphologies of the samples were observed by atomic force microscopy （AFM）. Scanning electron microscopy was used to detect the morphology of the bubbles, and the surface roughness was calculated. The effects of plasticizing length and gas injection delay on the surface quality of microcellular foam injection molding products were investigated. The results show that with the increase of injection time, the weight of the product decreases, and the volume of supercritical gas in the flow front decreases, and the surface quality is improved. With the increase of the plasticizing length, the surface thickness of the products without bubbles is also increased with the injection time unchanged.