Insert injection molding of low-density polyethylene single-polymer composites reinforced with ultrahigh-molecular-weight polyethylene fabric

Abstract

Low-density polyethylene single-polymer composites (SPCs) reinforced with sandwiched ultrahigh-molecular-weight polyethylene woven fabric were prepared by insert injection molding. The process combines aesthetic and processing advantages. A processing temperature window (135–155°C) of a very short cycle time (less than 30 s) could be realized. The mechanical properties and morphologies of the samples were evaluated. The results suggested that the polyethylene SPCs were prepared successfully with concurrent increases in flexural strength (∼57%), tensile strength (∼164%), and impact strength (∼69%). The effects of different processing parameters including the nozzle temperature, injection pressure, injection speed, and the holding time were discussed. Numerical simulation results were used in the analysis.

The mould for production of plastic spout cap with internal thread by injection moulding

“…Commercial materials have densities in range of 0.91 -0.94 g.cm -3 . LDPE is permeable to gases and vapours [5]. Very close tolerances are not possible with this material and its relatively large coefficient of thermal expansion makes it less suitable for long term applications.…”

“…Like HDPE, it is also susceptible to environmental stress cracking. For this material is recommended the injection pressure between 50 and 150 MPa and fast injection speeds [5,7,11]. Drying before processing is not necessary.…”

“…The possibilities and applications for utilizing injection moulding to produce plastic parts are seemingly infinite and offer manufacturers a cost effective method for producing reliable components [1][2][3]. Nowadays many components previously made of metallic materials are replaced by plastics thanks to the new technologies and improved material properties [4][5][6][7][8]. That is also the reason why we can meet plastics in many areas as well as in common usage at home [9,10].…”

Effects of Injection Molding Parameters on Properties of Insert-Injection Molded Polypropylene Single-Polymer Composites

“…The processing temperature window for PP SPCs and PE SPCs achieved 80 and 40 °C, respectively. A sandwiched structure with a middle fabric for PP and PE SPCs was also realized by the insert injection molding method [ 13 , 14 ]. This method can realize a better appearance because the fabric was set in the middle of the parts.…”

Natural fiber-reinforced high-density polyethylene composite hybridized with ultra-high molecular weight polyethylene

“…20 Additionally, its elongation at break is high and ranges from 3.5% to 4.5%. [19][20][21] Because UHMWPE is a polyethylene-based material, it has low melting temperature of approximately 142-150 C. 17,19,[22][23][24][25][26] UHMWPE has been used to reinforce HDPE, 27,28 low-density polyethylene, 19,20,[29][30][31] and thermoplastic starch. 32 All of these studies reported the significant strength improvement after UHMWPE fabric or fibers were added to the thermoplastic polymers.…”