High impact polystyrene rod

HONY®HIPS High impact polystyrene Introduction

Polystyrene is one of the oldest industrially produced thermoplastic polymers and is a very versatile product with a wide range of uses. This bright, pure amorphous plastic is easy to process, rigid, dimensionally stable and transparent, but its low impact strength limits its applications.

High-impact polystyrene is a small amount of polybutadiene grafted onto a polystyrene matrix. It has a "sea-island structure", the matrix is plastic, and the dispersed phase is rubber. Has many characteristics:

1. Impact-resistant polystyrene is a thermoplastic resin;

2. Odorless, tasteless, hard material, good dimensional stability after forming;

3. Excellent high dielectric insulation;

4. It is non-quality low water absorption material;

5. Its gloss is good and easy to paint. [1]

HONY®HIPS High impact polystyrene production method

There are two basic processes for HIPS production: batch process and continuous process. Both processes generally use pre-polymerization first. After the prepolymerization is complete, the polymerization is continued in suspension in a batch process and in solution in a continuous process. Therefore, the batch process is also called the bulk suspension process, and the continuous process is also called the solution process. [2]

Elastomers for HIPS

There are two main types of elastomers commonly used, one is low-cis polybutadiene rubber, and the other is high-cis polybutadiene rubber.

HONY®HIPS High impact polystyrene Performance

HIPS has the dimensional stability of general-purpose polystyrene (GPPS), but with better impact strength and rigidity. [4]

The relative density of HIPS is 1.04~1.06, and the heat distortion temperature is 70~84°C. The tensile strength of HIPS is about 15~30MPa, and the elongation is 35~60%. As the temperature decreases and the strain rate increases, it is a bit like a rubber toughened system. HIPS behave somewhat like viscoelastic solids, creeping when exposed to constant tensile stress. Creep decreases with increasing molecular weight and generally increases with increasing rubber content. The creep behavior of HIPS strongly depends on the average molecular weight (Mw). The bending strength is 29.4~50 MPa, the impact strength is 0.09~0.16N/M, the Vicat softening point is 84~100℃, and the melt index is 2~9g/10min. The heat resistance of HIPS components depends on their shape, production conditions, type of heat source and duration of heating, and is also affected by the HIPS level.

The properties of HIPS are not affected when exposed to water, alkali and dilute mineral acids. It can be swelled by some organic solvents and dissolved by others, which is determined by the difference in dissolution parameters between the continuous phase and the solvent phase. HIPS are particularly vulnerable to destruction when exposed to chlorinated and aromatic hydrocarbons. [4]

Reason for shock resistance

Impact-resistant polystyrene is an impact-resistant polystyrene product produced by adding polybutadiene rubber particles to polystyrene. This polystyrene product will add micron-sized rubber particles and connect polystyrene and rubber particles together by grafting. When impacted, the stress at the tip of the crack propagation is released by the relatively soft rubber particles. Therefore, the propagation of cracks is hindered and the impact resistance is improved.

HONY®HIPS High impact polystyrene Application

Due to the ease of manufacture and low cost, HIPS are widely used in many appliances and industries. Key industries and markets include packaging, disposables, appliances and consumer appliances, toys and entertainment, building products and decorative items. The largest single application of HIPS is packaging, especially in the food industry, with more than 30% of world consumption.