Insert injection molding of polypropylene single-polymer composites

Development and characterization of insert injection moulded polypropylene single-polymer composites with sandwiched woven fabric

“…For the insert injection moulding in this paper, the woven fabric was set in the middle of the cavity, so the surface appearance of the PP SPC samples could be the same as the non-reinforced PP samples. However, since high temperature in the middle of the flow can be kept for a longer time than the temperature near the cavity wall, in comparison with the previous studies [32,33], more fibres will be melted when the melt touches the sandwiched woven fabric. Therefore the highest nozzle temperature was chosen at 200 C. 1 180 64 5 10 2 180 48 15 30 3 180 32 25 20 4 190 64 15 20 5 190 48 25 10 6 190 32 5 30 7 200 64 25 30 8 200 48 5 20 9 200 32 15 10 T1 160 64 15 10 T2 170 64 15 10 T3 180 64 15 10 T4 190 64 15 10 T5 200 64 Fig.…”

“…It gives the feasibility to form SPCs even though the injection temperature is much higher than the melting temperature of the fibre. In our previous studies [32,33], the fabrics are set on the cavity wall, the temperature near the cavity wall leads to high viscocity then the matrix cannot infiltrate the fabric completely. Higher injection temperature could be used to improve the permeating of the matrix, but more fibres will be melted and the final sample still has the bad surface appearance with textile structure.…”

“…PP fabric is preplaced and affixed on the mould cavity wall using double-sided tape, and then PP matrix is injected into the cavity and infiltrates into the fabric by pressure. The mechanical strengths can be improved significantly, and the processing window can be up to 80 C [33]. However the infiltrating is incomplete because of the very low temperature at the cavity wall, and the remnant adhesive on the sample is difficult to clean.…”

“…However the thermoplastic elastomer is still not the same with PP, which would also influence the mechanical property. In our previous studies [32,33], the feasibility of preparing PP SPCs by insert injection moulding was investigated. PP fabric is preplaced and affixed on the mould cavity wall using double-sided tape, and then PP matrix is injected into the cavity and infiltrates into the fabric by pressure.…”

Preparation of hybrid poly(lactic acid)/flax composites by the insert overmolding process: Evaluation of mechanical performance and thermomechanical properties

“…This phenomenon occurred during the fabric overmolding process. [46][47][48] The paper covers the use of the overmolding method in the production of PLA-based composites reinforced with flax fibers. Due to the preliminary nature of the conducted research, the obtained materials were analyzed only in terms of their basic mechanical and thermomechanical properties.…”