In plastic injection OEM, the first thing to decide is often not the mold but "which material." PS, HIPS, ABS, PP and PC each have their own temperament — pick the wrong one and the part may crack, distort, or blow up your cost. This article covers the five plastics most common in electronics OEM, laying out their properties, pros and cons, and typical applications so you can settle the material with your vendor before tooling.
01Why material must be settled first
Material drives shrinkage, strength, heat resistance, appearance and cost. Shrinkage is the most critical — the mold dimensions are designed by back-calculating from the material's shrinkage, so changing the material usually means changing the mold. Settling the material before tooling is the first step to saving both money and time.
02The five plastics most common in electronics OEM
PS (polystyrene): transparent, rigid, low cost, easy to mold; downside is brittle and not impact-resistant. Suits transparent housings and low-cost disposable parts.
HIPS (high-impact polystyrene): PS modified with rubber, greatly improving impact strength while keeping good rigidity, moldability and reasonable cost. This is the mainstream material for SMD plastic reels and most electronic trays.
ABS: good toughness and surface finish, easy to electroplate or paint; medium heat resistance. Suits electronic housings, mechanical parts, and parts needing surface treatment.
PP (polypropylene): chemical- and fatigue-resistant (can form living hinges), low density, low cost; but lower rigidity, high shrinkage and prone to distortion. Suits returnable bins and parts with movable snap fits.
PC (polycarbonate): high strength, impact- and heat-resistant, high transparency; downside is high cost, poorer flow, and sensitivity to processing conditions. Suits high-strength transparent parts and safety-related parts.
03How to choose quickly
- Transparent and cheap → PS; transparent and drop-resistant → PC
- Electronic trays, reels → HIPS
- Housings needing paint and finish → ABS
- Chemical resistance, movable snap fits → PP
- High strength, safety parts → PC
These are just broad directions. In practice you also weigh heat resistance, flame retardancy, food-grade and other requirements, then pick a finer grade.
04Don't forget electrical properties (ESD) and color
Electronic parts often need anti-static or conductive properties, achievable by adding modifiers to base resins such as PS, HIPS and ABS, with the grade chosen by the component's ESD sensitivity — for the selection logic see Anti-Static / Conductive / Insulative ESD Type Selection. Color can be customized by Pantone or a color chip.
05When unsure, just ask
For the material question, rather than guessing, organize the part's application, strength requirement, heat resistance, appearance requirement and estimated volume, and tell us via online inquiry; we will recommend the material and process directly. To then learn the design points once the material is set, see Injection Part Design DFM Essentials.