Polypropylene injection molding parameters

SF Xavier, D Tyagi, A Misra. Influence of injection-molding parameters on morphology and mechanical properties of glass fiber-reinforced polypropylene composites. Polymer Composites 3 88-96, 1982. 

The method of incomplete mold filling is effective for investigating injection molding of fiber glass-loaded polypropylene and polystyrene melts.283 After solidification, samples were prepared for microscopic investigation. The authors determined the distribution and orientation of the fibers in different sections of the article and thus were able to clarify the pattern of flow in different parts of the mold as a function of the process parameters. They concluded that the width of the (cavity)... 

R R. Jones, Handbook of polymer-fiber composites. New York Langman, 1994, p. 78. A. K. Bledzki and O. Faruk, Effects of the chemical foaming agents, injection parameters, and melt-flow index on the microstructure and mechanical properties of micro-cellular injection-molded wood-fiber/polypropylene composites. Journal of Applied Polymer Science, 97,1090-1096 (2005). 

X.GUO, A.I.Isayev, and L.Guo. Crystallinity and Microstmcture in Injection Moldings of Isotactic Polypropylenes. Part I A New Approach to Modeling and Model Parameters. Polymer engineering and science. 1999,39 (10), 2096-2114... 

The effect of the injection molding process conditions (melt and mold temperatures, holding/packing pressure and injection velocity) over the adhesion resistance of two overmolded materials was studied. The materials used were a Thermoplastic Vulcanized Elastomer (TPV) (Santoprene 8211-55) and a Polypropylene (PP) (Moplen HP501H). The measurement of the adhesion resistance was done by Tensile Test and it was observed that the melt and mold temperature are the parameters that affect in greater degree the adhesion resistance. 

This paper will examine the scratch whitening resistance of PP rich, injection molded Thermoplastic Polyolefins (TPOs) for exterior automotive applications. Significant attention will be given to the influence of the molecular architecture of the polypropylene (PP) component on the surface morphology and resultant scratch whitening resistance of the injection molded part. Material parameters and surface crystallinity which contribute to enhanced scratch whitening resistance will be highlighted. 

Water-assisted injection molding experiments were carried out on newly developed equipment in our lab. The effects of four processing parameters, short-shot size, melt temperature, water injection delay time, and water pressure, on the water penetration length and residual wall thickness of water-assisted injeetion molded polypropylene curved pipe were investigated. The crystallization behavior difference between the beginning and the end of the water channel of the eurved pipe was analyzed using differential scanning calorimetry. 

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