Plastic Material Customization: From Raw Material Selection to Finished Product Delivery

Why Customize Plastic Materials?

Off-the-shelf plastic materials often cannot meet the specific requirements of modern product designs. 

Customization allows engineers to achieve:

- Exactly the right balance of mechanical properties

- Specific regulatory compliance (UL, RoHS, REACH)

- Processing optimization for specific mold designs

- Cost optimization by avoiding over-engineering

- Unique surface finish and color matching

At Wenzhou Wohua Plastic, we provide end-to-end customization: from modifying the base material formulation 

to producing finished injection-molded parts.

   Material Selection: The Foundation

Material selection is the most critical step in any plastic product development. The wrong material can 

lead to product failure, costly mold modifications, or production delays.

  Selection process:

1. Define application requirements (temperature range, mechanical loads, chemical exposure, regulatory standards)

2. Determine critical properties (tensile strength, HDT, impact resistance, UL94 rating)

3. Select base polymer family (PA, PC, POM, PP, ABS, etc.)

4. Specify modification type (GF, FR, IM, UV, etc.)

5. Define color and surface requirements

  Our recommendation: Send us your drawing with a brief description of the use environment. Our technical team will 

recommend the optimal material grade within 24 hours.

   Mold Design and Manufacturing

The mold is the heart of any injection molding project. A well-designed mold ensures consistent part quality, dimensional 

accuracy, and long production life.

  Mold design considerations:

- Gate location and type (affects weld lines and fill pattern)

- Cooling channel design (affects cycle time and part warpage)

- Ejection system (affects part release and surface quality)

- Venting (prevents gas traps and burn marks)

- Steel selection (affects mold life and maintenance)

  Typical mold production timelines:

- Simple molds (single cavity, basic geometry): 7-15 days

- Standard molds (multi-cavity, moderate complexity): 15-25 days

- Complex molds (slides, lifters, tight tolerances): 25-40 days

We provide mold flow analysis (Moldflow) before steel cutting to identify potential issues.

   Injection Molding and Quality Control

Once the mold is ready, we proceed to the production phase with rigorous quality control at every stage.

  Our QC process:

1. Incoming inspection: Raw material verified against specification

2. First article inspection (FAI): Complete dimensional and functional check of first production pieces

3. In-process inspection (SPC): Regular sampling during production to maintain statistical process control

4. Outgoing inspection: Final quality check before shipment

  What we measure:

- Critical dimensions (CMM, optical comparators)

- Mechanical properties (tensile, flexural, impact)

- Visual inspection (color, surface finish, flash, sink marks)

- Functional testing (fit, assembly, leak test where applicable)

Sample approval process: Trial samples are produced and sent for your review. We do not start mass production 

until you approve.

   Flexible MOQ and Scalable Production

One of our key advantages is production flexibility:

  Small batches (dozens to hundreds):** Ideal for prototypes, market testing, and new product launches. Minimum 

order quantity as low as 50-100 pieces.

  Medium production (thousands):** Standard production runs with established process parameters.

  Volume production (tens of thousands+):** Optimized processes, automated quality control, competitive per-piece pricing.

We support production scale-up: start with small batch testing, then scale to full production as your market grows.

   Case Example: From Sketch to Shipping

A recent project illustrates our full-service capability:

A startup company needed a custom plastic enclosure for a portable medical device. They had a rough 3D-printed 

prototype and a list of functional requirements.

  Our process:

1. Material selection: Recommended medical-grade PC/ABS for impact resistance and sterilization compatibility

2. Mold design: Single-cavity prototype mold initially, then production 2-cavity mold

3. Sampling: 10 samples produced in 12 days from drawing approval

4. Testing: Customer conducted functional and biocompatibility tests

5. Production: Started at 500 pieces/month, scaled to 5,000 pieces/month within 6 months

From first conversation to first shipment: 35 days.

   Why Choose Wohua Plastic for Customization?

Material advantage: Direct supply of KINGFA and HIGHSUN virgin materials at competitive prices.

Technical expertise: Years of experience across automotive, electronics, medical, and industrial sectors.

Fast response: Drawing evaluation within 24 hours.

Flexible MOQ: From prototype quantities to volume production.

One-stop service: Material selection, mold design, injection molding, QC, assembly, and logistics.