Polypropylene plastic VS ABS plastic

A Comparative Analysis of Polypropylene VS ABS

The chemical name of ABS plastic is acrylonitrile-butadiene-styrene copolymer, and its English name is Acrylonitrile Butadiene Styrene.

The chemical name of PP plastic is polypropylene.

PP is non-toxic, odorless, and has low density, and its strength, stiffness, hardness, and heat resistance are better than low-pressure polyethylene. It can be used at around 100 degrees. It has good electrical properties and high-frequency insulation and is not affected by humidity, but at low temperatures, It becomes brittle, not wear-resistant, and easy to age. It is suitable for making general mechanical parts, corrosion-resistant parts, and insulating parts. Common acid and alkali organic solvents have almost no effect on it and can be used in tableware.

ABS has excellent mechanical properties, its impact strength is excellent, and can be used at extremely low temperatures; ABS has excellent wear resistance, good dimensional stability, and oil resistance, and can be used for bearings under medium loads and speeds. The creep resistance is greater than that of PSF and PC, but smaller than that of PA and POM. The flexural strength and compressive strength of ABS are poor among plastics. Mechanical properties are greatly affected by temperature. The heat distortion temperature of ABS is 93~118℃, and the product can be increased by about 10℃ after annealing treatment. ABS can still show a certain degree of toughness at -40°C and can be used in the temperature range of -40~100°C.

Physical properties

PP plastic: usually a white waxy material with a transparent and light appearance. It has good heat resistance, its melting point is roughly between 164 and 170°C, and it can soften at about 155°C. Its operating temperature range is -30 to 140°C. PP plastic has a low density and is the lightest among commonly used resins.

ABS plastic: Appearance is opaque and ivory-colored pellets. It is non-toxic, tasteless and has low water absorption. Its products can be dyed in various colors and have a high gloss of 90%. The toughness, temperature resistance and surface gloss of ABS plastic are generally better than PP plastic.

Chemical properties

PP plastic: It can resist the corrosion of acids, alkalis, salt liquids and various organic solvents below 80℃, and can decompose under high temperature and oxidation. It has good chemical stability and does not interact with most chemicals except strong oxidants.
ABS plastic: It has the common properties of three components, namely the chemical corrosion resistance and heat resistance of acrylonitrile, the high elasticity and toughness of butadiene, and the processing and molding characteristics of styrene’s thermoplastic plastics and improved electrical properties.

Forming and processing

PP plastic: The molding temperature is usually between 160-220°C, the specific gravity is 0.9-0.91 g/cubic centimeter, and the molding shrinkage rate is 1.0-2.5%.
ABS plastic: Molding temperature is usually between 200-240℃, and drying conditions are 80-90℃ for 2 hours. Due to its excellent comprehensive properties, ABS plastic is widely used in machinery, electrical, textile, automobile, and other fields.

ABS plastic, like PS, is a thermoplastic with excellent processing properties and can be processed with common processing methods. The melt fluidity of ABS is better than PVC and PC, but worse than PE, PA, and PS, and similar to POM and HIPS; the flow characteristics of ABS are non-Newtonian fluids; its melt viscosity is related to processing temperature and shear rate, but is more sensitive to shear rate.

Properties after burning

PP plastic: Burns quickly and easily, melts and drips, the flame is yellow above and blue below, and smells like petroleum.

ABS plastic: slow softening and burning, no dripping, yellow flame, black smoke, bright surface after fire.

Density

PP has a smaller density than ABS. So ABS is lightweight but tends to be a bit heavier than polypropylene

Hardness

ABS material has high hardness. The surface hardness of PP is low among the five general plastics, only better than PE. When the crystallinity is higher, the hardness also increases accordingly, but it is still not as good as PVC, PS, ABS, etc.

Electrical properties

The electrical insulation of ABS is better than that of PP, and it is not affected by temperature, humidity and frequency.

Price

The price of ABS material is relatively high. This is because ABS has better performance and wider uses, and its production cost is also higher. In comparison, the price of PP material is relatively low because of its low production cost and wide range of uses.

Gloss

The appearance of ABS is opaque and ivory-colored granules with high gloss, generally reaching more than 90%.
The glossiness of PP varies depending on the type. For example, the gloss of highly transparent PP can reach 129.2%, while the gloss of homopolymer PP is only 99.6%. Although the gloss of homopolymer PP is slightly lower than ABS, the gloss of highly transparent PP is better than ABS.