Influence of length of glass fibers in recycled polypropylene on tensile properties

The purpose of this article is to show the influence of grinded glass fibers in polymer material. Tested samples were processed by injection molding. Waste from this production was subsequently ground and a mixture was obtained with different size of crushed material. These particles contains glass fibers of similar length as the specific size of particle. Thus very small particles contain very short fibers. Investigation was carried out by testing tensile properties on material polypropylene with 30% glass fibers. Testing was conducted at ambient temperatures. The effect of reprocessing of material is mainly represented by fiber shortening. As a result, considerable reduction of tensile properties can be observed. The reduction is most evident in the modules of elasticity and ultimate tensile strength.