The Dispersion And Its Evaluation Of Fiber In The Theroplastic Composites By Wet Process

Because of the lighter mass, the higher strength and the recycling, the fiber reinforced thermoplastic composites have widely used recently. But the dispersion of fiber in materials has high affect on its behavior.The fiber reinforced thermoplastic materials has been made by the stirring equipment which designed and made by ourselves. The materials, formed by certain length CF, were dispersion in the stirring tank, then dried and molded by the compression molding. The factors work on the fiber dispersion containing the fiber length, the stirring time, the fiber contents, and the assistant operation. Then, the mechanical properties, the resistance, and the water absorption were tested. The fractal was studied, and applied in the evaluation of the fiber dispersion.It was found that the mechanical properties was not obviously improved when the fiber contents increased from 1%～5%. The percolation threshold of resistance appeared in 3wt%～4wt% fiber contents. It said that the longer the fiber was, the worse the fiber dispersion was; the long the stirring time was, the better the fiber dispersion was; and the higher the fiber contents were, the worse the fiber dispersion was.The fractal was calculated by the box-counting method. The results showed that, when the fiber length was 3mm, stirred for 10min, and under the ultrasonic, the maximum fractal dimension was got,1.88. As the resistance, the factors like the stirring time, the fiber contents, the fiber length, and the assistant had the similar affection on the fractal dimension.