Adhesion between thermoplastic elastomers and polyamide‐12 with different glass fiber fractions in two‐component injection molding

Abstract

The usage of thermoplastic elastomers (TPEs) is increasing, and integrated hard‐soft parts can be mass produced by two‐component injection molding (or sequential molding). A key property of such parts, the adhesion between the two materials, is the topic of this study. The hard part (the first molded component) in this study was polyamide‐12 with 0 to 50 wt% glass fibers (PA12‐GF). As the second component, two TPEs were used: a vulcanized TPE and a styrenic TPE, both modified for adhesion to polyamides. The adhesion, assessed by 90° peel tests, increased with increasing melt temperatures and TPE injection rate, while it decreased with increasing glass fiber fraction in the PA12‐GF. Based on characterization of cross‐sections and fiber distributions near the interface, we propose some hypotheses for the effect of fiber fraction on the fusion between PA12‐GF and TPE. These hypotheses involve the near‐surface properties of the PA12‐GF materials, microstructure, thermo‐mechanical properties, and thermal properties. A direct effect of increasing the glass fiber fraction, that is, a reduction in adhesion as more fibers are present at the interface, does not seem to be a major effect, since few fibers are in direct contact with the TPE for any fiber fraction.

Investigating the mechanical properties and microstructure of the weld joint obtained by laser welding of PA12/CNT nanocomposites

“…[1][2][3] In recent years, polyamide (PA) has attracted enormous attention, owing to its good processability, high mechanical properties, and high thermal stability. [4][5][6][7] Among the various polyamide grades, polyamide 12 (PA12) has found significant applications in different industries, because it has good dimensional stability, small shrinkage rate, easy processing, and low melting point. [8,9] In order to increase the mechanical and thermal properties of PA12, it was recommended to add a small amount of filler like carbon nanotube (CNT).…”

Circular Production, Designing, and Mechanical Testing of Polypropylene-Based Reinforced Composite Materials: Statistical Analysis for Potential Automotive and Nuclear Applications

“…The well-established injection molding technique is mostly used commercially for the recycling of polymer wastes [ 64 , 65 ]. This technique enables the processing of different thermoplastics [ 66 ], thermosetting [ 67 ], and elastomers [ 67 , 68 ]. However, parameters like impurities in wastes [ 69 ], moisture [ 70 ], heating time [ 71 ], chemical reactions [ 72 ], and thermodynamic functions cause operational problems [ 73 ].…”

Optimizing the mechanical properties of TiO2/PA12 nano‐composites fabricated by SLS 3D printing

“…[8,9] The most widely applied polymer in the SLS process is Polyamide (PA), which is due to its good processability, high thermal stability, and excellent mechanical properties. [10][11][12][13] However, the addition of nano-particles into PA12 matrix can improve the mechanical properties of this polymer, because the nanoparticles have a high specific surface area that can act as a stress-transfer interface. One of the most significant nano-particles is titanium dioxide (TiO 2 ) due to some features such as photocatalytic activity, antibacterial activity, odor inhibition, photoelectric conversion, and selfcleaning mechanism.…”