High-density polyethylene shrinkage

Porter, R.S. Daniels, M. Watts, M.P. Pereira, J.R DeTeresa, S. Zachariades, A. Shrinkage as a measure of the deformation efficiency of ultra-high density polyethylene. J. Mater. Sci. Lett. 

Hyperfom HPN 210 M is a new nucleating agent for injection molded high-density polyethylene apphcations. It improves mechanical performance to the levels approaching those of polypropylene impact copolymers. It increases stiffness by up to 50%, heat distortion temperature by 10-40°C, and productivity. It has ability to create lamellar crystal orientation of PE in the polymer flow direction reducing shrinkage. ... 

Once a part had been designed, the student was asked to pick a generic type of material. Their choices were high-density polyethylene, low-density polyethylene, polypropylene, filled polypropylene, polystyrene, high-impact polystyrene, thermoplastic elastomers, nylon, polyester, acetal, polycarbonate, or acrylic. This guaranteed that there would be both a wide diversity in process and shrinkage behaviors. The students were... 

The commercially important properties of Et>-Nb copolymers include low density, high transparency and low color, high moisture barrier and low moisture absorption, low optical distortion, excellent feature replication, resistance to polar solvents, high purity, shatter resistance, good biocompatibiUty, extremely low dielectric loss, high temperature capability, and compatibility with polyethylenes. The resins also have the low shrinkage and warpage typical of amorphous polymers. 

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