Excellent all-around qualities of PET engineering plastics include great mechanical strength, low creep, outstanding heat resistance, and good electrical insulation. They can take the role of metals as structural engineering materials since they last a long time in hard chemical and physical environments. employ. PET is a popular engineering plastic that is tough, performs well, and is one of the five main types.
The heat resistance, modulus, toughness, dimensional stability, and flame retardancy of PET plastic can all be markedly increased by reinforcing, alloying, and adding flame retardants. The series include halogen-free flame retardant, high gloss enhanced flame retardant, color stable enhanced flame retardant, low warpage enhanced flame retardant, increased toughening grade, and enhanced flame retardant. Many industries, including electronics, automotive, and home appliances, use modified PET polymers.The primary techniques for PET alteration are as follows:
1. Modification of PET filling
Using inorganic components that have entirely different properties from the polymer matrix, filling modification is one of the simplest and most efficient ways to improve a material’s performance overall.
2. PET modified by nanoparticles
The field of research on modifying PET composite materials with nanoparticles is currently quite advanced. Ke et al. modified PET using layered clay, resulting in PET/clay nanocomposites through intercalation polymerization. The study’s findings indicate that at 5 weight percent of clay, the composite material’s thermal deformation temperature increases by 20 to 50 degrees Celsius when compared to pure PET, and its modulus increases by roughly double that of PET.
3. PET modified with glass fiber
Micron-sized glass fibers (GF) are utilized extensively to fill modified polymer materials due to their exceptional cost and controllability benefits over nanoparticles.
4. PET blending modification
To create a polymer alloy or blend with new qualities, two or more polymers, including PET, are melted and blended in the right amount under specific circumstances like temperature and shear stress. The preparation of such polymers depends critically on the compatibility of the polymers.
5. PET treated with polyolefin
PET and PE are incompatible due to their blatantly different chemical structures. It was discovered from the study of simple binary blending of the two that compatibilization is necessary to increase the two’s compatibility and therefore enhance the impact properties of PET by blending modification of polymers. The impact strength of the EVA and EAA systems is enhanced in the HDPE and PET blend system.
By combining the benefits of both PET and PP, an alloy is created that performs better. For instance, PP can lessen PET’s sensitivity to moisture while PET can increase PP’s heat resistance. Without the use of a compatibilizer, there is very little bonding between the two phases and very poor mechanical qualities when PET and PP are combined.
In order to achieve blending and compatibility, a compatibilizer must be introduced because PET/PS is an incompatible system. It was discovered in the study that by using styrene and glycidyl acrylate copolymer P (S-GMA) as a reactive compatibilizer into the PET/PS blending system, the mechanical properties of the PET/PS/P (S-GMA) blending system were enhanced and there was good interfacial bonding.
6. PET modified with polyester
In the 1970s, PBT, a brand-new kind of technical plastic, emerged quickly. It is more durable and moldable than PET, and its mechanical qualities are superior. Its fluidity and heat resistance, however, are inferior than PET’s. Good yet more expensive. Teijin claims that the combination of the two has low molding shrinkage and strong impact resistance when 0.5% talcum powder is added as a nucleating agent.
PC has good toughness, high glass transition temperature, and good mechanical qualities; but, its aging resistance and fluidity are weak. PC and PET used together can increase impact strength. Blends of the two are frequently found in vehicle parts and have been industrially made elsewhere.
7. Modified PET with elastomer hardened
Right now, one of the most popular polymers is ABS. It is superior to HIPS in terms of general qualities as well as toughness. Combining PET and ABS can increase PET’s resistance to impact.
The study discovered that heat and leftover catalyst impurities in ABS are related to the hydrolysis of the PET chain, and that the relative molecular weight of PET in the mix is highly sensitive to the processing temperature. Without influencing the modulus and flexural strength, the drop in the relative molecular weight of PET will result in a significant loss of impact characteristics and ultimate elongation.
