Summary of thermo-oxidative aging test conditions and performance comparison for different thermoplastic compositesa.
| Composites | Oven temperature (°C) | Test durations | Heat stabilizers/antioxidant/additives used | Results | Ref. |
|---|---|---|---|---|---|
| LGF/PA6 | 160 | 10, 20, 30, 40 and 50 days | Copper salt, phosphorus acid | The presence of stabilizers showed better retention in terms of dynamic and static mechanical properties | 78 |
| GF/PA6, talc/PA6, BioC/PA6 | 140 | 1000 h (ISO 188:2011 standard) | — | GF/PA6 composite retained better mechanical prop. than talc/PA6 and BioC/PA6 composites | 187 |
| GF/PA6, CF/PA6 | 90, 130, 150 and 180 | 200, 400, 800 and 1600 h | — | CF showed better stabilizing effect than GF in long-term TOA test | 183 |
| Sago starch/LDPE | 70 | 1, 2, 3 and 4 weeks | SBR, ENR-50, MnS as pro-oxidant | Pro-oxidant i.e. unsaturated elastomer and metal salts enhanced the degradation rate of the biocomposites | 188 |
| GF/PBT, talc/PBT, BioC/PBT | 155 | 1000 h (ASTM D3045-92 standard) | — | GF/PBT showed the most stable in retaining its mechanical properties after TOA as compared to talc/PBT and BC/PBT | 185 |
| LGF/PA10T | 160 and 200 | 10, 20, 30, 40 and 50 days | — | Decline in mechanical performance due to interface debonding of the composite | 189 |
| iPP, HMS-PP | 90 | 6, 12 and 20 days (ASTM D 3045-2003 standard) | Irradiation with gamma rays | Irradiated samples indicates less TOA degradation as compared to neat iPP | 190 |
| PVC/NBR thermoplastic elastomers | 100 | 3, 7, 14 and 21 days (BS 7646 standard) | — | Crosslink density increases with aging time | 191 |
| Mechanical prop. Increase and decrease after reaching maximum as the aging test continue | |||||
| HIPS, HIPS-FR | 80 | 1400 h | Fire retardant, deca-bromodiphenylether (deca-BDE) | HIP containing deca-BDE improved aging prop. | 184 |
| Flame retardant behaviour of HIPS-FR is retained even after aging | |||||
| TPO-based biocomposites | 110 | 250, 500, 750 and 1000 h (ISO 188-2011 standard) | Irganox, Songxtend anti UV additive (Tinuvin P) | The incorporation of phenolic antioxidants provide good resistance to TOA degradation | 192 |
| SGF/PPS | 140, 160, 180 and 200 | 5300 h | — | Degradation rate increases with increasing the TOA temp. | 193 |
| Fatigue life decreases after aging due to oxidation | |||||
| Metal salt/PA6,6 | 110 | 7000 h | Metal salts | Zn, Cu and mixture of CuCl2/KI showed effective long-term stabilizer which could prevent oxidative propagation reactions during TOA | 91 |
a
Abbreviation: LGF: long glass fibre; GF: carbon fibre; BioC: biocarbon; TOA: thermo-oxidative aging; SBR: styrene butadiene rubber; ENR-50: epoxidised natural rubber with 50 mol% epoxidation; MnS: manganese stearate; PBT: PA10T: poly(decamethylene terephthalamide); iPP: isotactic polypropylene; PVC: poly(vinyl chloride); NBR: nitrile butadiene rubber; HMS-PP: high melt strength polypropylene; HIPS: high impact polystyrene; FR: flame retardant; deca-BDE: deca-bromodiphenylether; TPO: thermoplastic polyolefins; SGF: short glass fibre; PPS: polyphenylene sulfide.