PP

PP (polypropylene) -Focus here on engineering applications

Application scenarios: automobile parts (bumper, interior panel, dashboard, battery box), household appliance shell, turnover box/logistics box, pipe, thin wall packaging, fiber (non-woven fabric, carpet silk).

Appropriate additives and functions:

Nucleating agent: Core additive! (Almost all injection/extrusion applications)

α-Nucleating agent: improve rigidity, heat deformation temperature, dimensional stability, shorten the molding cycle (such as automotive parts, turnover boxes).

β-Nucleating agent: significantly improves impact toughness (especially low-temperature impact) and improves stress crack resistance (e.g., pipes, automotive parts requiring toughness).

Transparent nucleating agent: used for transparent PP products (food packaging, medical devices), improve transparency and gloss.

Thickener (peroxide/epoxy):

Overoxides: Controlled rheology (CR-PP), reduce molecular weight viscosity, improve processing flow (spinning, thin wall injection), but at the expense of some mechanical properties.

Epoxy: (mainly used for recycling PP and blends) repair degraded chains, improve melt strength and toughness, and improve processing stability.

Anti-hydrolysis agent (carbodiimide): (for special high humidity environment application, recovery of PP) PP itself is very resistant to hydrolysis and generally does not need to be added. However, in extreme conditions or unstable performance of recovery material, it can be considered to add to improve long-term reliability.

Lubricating masterbatch: (high speed processing, high filling PP, reduce precipitation) Improve processing fluidity, increase production, reduce die accumulation and friction heat, reduce energy consumption, improve surface gloss (reduce glass fiber/filler exposure), reduce the precipitation of slipper/slipper.

Toughening masterbatch: (Automobile bumper, parts with high impact resistance) It is provided in combination with or directly with elastomers (POE/EPDM), which greatly improves the impact strength. It is the key to toughening PP formulation.

Anti-aging masterbatch: (Automobile exterior parts, turnover boxes, outdoor furniture) Essential! PP is prone to photo-oxidation aging. Composite antioxidant (resorcinol + phosphite/thiophosphite) and light stabilizer (HALS/UV absorber) masterbatch prevent yellowing, powdering, and brittleness, extending outdoor service life.