Flow of short‐glass‐fiber‐filled thermoplastics in channels of circular of thin rectangular cross‐section

Abstract A pressure‐flow‐type modular rheonmeter was developed specifically for the stuidy of the flow of unfilled thermoplastic melts and for the same melts with particles of relatively large dimensions in channels of shapes and dimensions encompassing those encountered in the injections molding of commercial parts. Experimental results are reported here for the case of polypropylene with 20 and 40 percent by weight of short glass fibers. The handling of the wide range of data, suing the concept of an end correctuion(Bagley plot), led to a reasonably unique viscosity vs. Shear‐rate relationship for each material and confirmed that fibers have little effect on such a relationship for the range of shear rates involved in commercial processing. End effects were examined systematically for the wide range of shear rates and geometries, and the data, although difficult to correlate at present, should prove useful to rheologists trying to elucidate the flow in such areas.