Influence of Different Stabilization Systems and Multiple Ultraviolet A (UVA) Aging/Recycling Steps on Physicochemical, Mechanical, Colorimetric, and Thermal-Oxidative Properties of ABS

Abstract

Commercially mass-polymerized acrylonitrile–butadiene–styrene (ABS) polymers, pristine or modified by stabilization systems, have been injection molded and repeatedly exposed to ultravilolet A (UVA) radiation, mechanical recycling, and extra injection molding steps to study the impact of such treatments on the physicochemical, mechanical, colorimetric, and thermal-oxidative characteristics. The work focus on mimicking the effect of solar radiation behind a window glass as relevant during the lifetime of ABS polymers incorporated in electrical and electronic equipment, and interior automotive parts by using UVA technique. The accelerated aging promotes degradation and embrittlement of the surface exposed to radiation and causes physical aging, deteriorating mechanical properties, with an expressive reduction of impact strength (unnotched: up to 900%; notched: up to 250%) and strain at break (>1000%), as well as an increase in the yellowing index (e.g., 600%). UV-exposition promotes a slight increase in the tensile modulus (e.g., 10%). The addition of antioxidants (AOs) leads to a limited stabilization during the first UVA aging, although the proper AO formulation increases the thermal-oxidative resistance during all the cycles. Mechanical recycling promotes an increase in strain at break and unnotched impact strength alongside a slight decrease in tensile modulus, due to disruption of the brittle surface and elimination of the physical aging.

Investigation of the Mechanical Properties of Parts Fabricated with Ultrasonic Micro Injection Molding Process Using Polypropylene Recycled Material

“…These experimental TGA curves confirm that UMIM modifies the material molecular structure, which agrees with the findings of Refs. [ 9 , 10 ]. The specimen section C (the furthest from injection gate) developed properties very similar to those of the virgin pellets, while the material located close to section A, experience the highest molecular weight loss.…”

“…They concluded that antioxidants added in sufficient amount during the original material processing reduce thermal-oxidative degradation improving the recycled material physical and chemical properties. In addition, Fioro et al [ 9 ] studied ABS polymer degradation with different stabilization systems and repeatedly exposed the injected molded parts to ultraviolet A radiation, and mechanical recycling, in order to investigate the impact of these treatments on the physicochemical, thermo-oxidative, and mechanical properties. They found that mechanical recycling increases the injected molded parts strain at break with a slight decrease in the tensile modulus.…”

Application of Selective Induction Heating for Improvement of Mechanical Properties of Elastic Hinges

“…Polymer materials are currently widely used in many industries, such as medical, electronics, automotive and building [ 1 , 2 ]. The popularity of polymers is associated with relatively low prices, a very good price-quality ratio and general availability [ 3 ].…”

Comparison of Selected Parameters of a Planetary Gearbox with Involute and Convex–Concave Teeth Flank Profiles

“…The selection of the right production structure is the key polyethylene terephthalate (PBT), polyacetal (POM), etc. [35][36][37]. In addition, polymer composites can be used for various parts of a vehicle body or, for example, gearbox housings [38][39][40][41].…”