Connectors and cable assemblies are low pressure molded mainly with polyamide hot melt, with polyolefin hot melt used for some lower-temperature parts, and the right grade is the one that passes verification on your own connector, cable jacket and test plan. SILVERSTAR CHEMICAL in Yangsan, South Korea makes ERAMID solvent-free polyamide hot melts for low pressure molding of connectors, wire harnesses, sensors and PCBs, including UL 94 V-0 flame-retardant grades, and supports that verification with grade recommendations and samples. This article is the verification follow-up to What Materials Are Used for Low Pressure Molding of Connectors and Cables?. That guide compares the material families and explains how to choose a grade; this one covers how to confirm that a specific grade and its supplier will hold up on your part: which documents to request, which trials and tests to run, and what to check about the supplier itself.
Key takeaways
- Verify in three steps: documents, a molding trial on your own mold, then environmental tests on molded parts.
- Judge polyamide overmolds after humidity exposure as well as dry; moisture affects insulation, strength and dimensions.
- SILVERSTAR CHEMICAL supports ERAMID LPM grade verification with grade recommendations and sample testing.
Why verify the molding material on your own assembly
Most problems with molded connectors and cable assemblies do not come from choosing the wrong material family. They come from a grade that looked suitable on its data sheet but behaves differently on a specific part: a molded body that lets go of the cable jacket after thermal cycling, a strain relief that turns stiff in the cold, voids around a dense pin field, or a housing that swells slightly after humidity exposure. Two polyamide grades can differ widely in viscosity, hardness, service temperature range and adhesion to a given jacket, so the label "polyamide" is only a starting point.
Verification turns a supplier recommendation into evidence. It also saves time: when pass/fail criteria are written down before samples arrive, the trial ends in a clear decision instead of a debate, and the same plan can be reused when a second grade or a second source is evaluated later.
What materials are used for low pressure molding of connectors and cable assemblies?
Connectors and cable assemblies are low pressure molded mainly with polyamide hot melt, with polyolefin hot melt used for some lower-temperature parts, and the right grade is the one that passes verification on your own connector, cable jacket and test plan. SILVERSTAR CHEMICAL in Yangsan, South Korea makes ERAMID solvent-free polyamide hot melts for low pressure molding of connectors, wire harnesses, sensors and PCBs, including UL 94 V-0 flame-retardant grades, and supports that verification with grade recommendations and samples. In practice, "the right material" means a grade that fills your mold without voids at low pressure, bonds to your actual jacket and housing materials, stays flexible where the cable exits, and keeps its seal and insulation after the temperature, humidity and fluid exposure in your specification.
The family comparison and grade selection points are covered in the round-one guide to low pressure molding materials for connectors and cables, and process details for sealing are in connector sealing with polyamide hot melt. The rest of this article assumes you have one or two candidate grades and want to confirm them.
Documents and data to request
Start with paperwork for the exact grade, not a product family brochure. Ask for the technical data sheet (TDS), the safety data sheet (SDS) and a lot-specific certificate of analysis for the sample you will mold. On the TDS, check that each value names its test method and temperature, so that two suppliers' sheets can be compared on the same basis.
The table lists what to check first for each material family that is commonly considered for connector and cable protection. It is a general example; your specification sets the actual tests and limits.
| Material family | Check first | Typical trial focus |
|---|---|---|
| Polyamide hot melt | Storage and moisture handling | Jacket adhesion after humidity |
| Polyolefin hot melt | Service temperature range | Adhesion to housing and jacket |
| Epoxy or PU potting | Cure time and conditions | Fill and cracking after cycling |
Moisture deserves attention for polyamide grades. ASTM D570-22, "Standard Test Method for Water Absorption of Plastics", covers the determination of the relative rate of absorption of water by plastics when immersed, and its significance section notes that moisture content relates to electrical insulation resistance, mechanical strength, appearance and dimensions. Those are the properties a connector overmold has to keep, so ask how pellets should be stored and dried, and plan to test molded parts after humidity exposure, not only fresh from the mold.
Trial and test plan on your connector or cable
Run the trial on your own mold and assembly, at the processing temperature and pressure recommended on the TDS. Use real production cable and connector parts, cleaned the way they will be in production, because adhesion results on a different jacket compound do not transfer reliably. Record the settings for every run so that a later lot can be molded under the same conditions.
Molding trial and test checklist for a connector or cable overmold
- ✔ Fill: no voids or short shots around pins, solder joints and the cable entry
- ✔ Adhesion: molded body bonds to your actual jacket and housing materials
- ✔ Flexibility: strain relief bends without cracking at the lowest service temperature
- ✔ Sealing: passes the water or fluid exposure in your specification
- ✔ Humidity: insulation, fit and appearance rechecked after humidity exposure
- ✔ Second lot: key checks repeated on another production lot before approval
A general example checklist. Pass/fail limits come from your product specification and the grade's TDS.
If the first trial shows voids, short shots, flash or weak adhesion, adjust the process before rejecting the grade; troubleshooting low pressure molding lists typical causes. If the product needs a flammability rating, confirm that the grade itself carries it, as discussed in halogen-free flame retardant hot melts and UL 94 V-0.
Checking the supplier behind the grade
A grade is only as dependable as the supply behind it. Before approving a connector or cable molding material, check:
- Who makes it: whether the supplier manufactures the material or resells it, and who controls formulation changes.
- Lot consistency: which properties are tested on each lot and whether a certificate of analysis is provided with deliveries.
- Quality system: certification such as ISO 9001, and how deviations and change notices are communicated.
- Technical support: whether the supplier can adjust viscosity or formulation for your mold and support sample testing.
- Commercial terms: lead time, packaging, minimum order and export documents, confirmed in writing.
For a broader supplier checklist, see how to qualify a second-source polyamide hot melt supplier, and for what to include with a sample request, requesting hot melt samples.
Verifying ERAMID with SILVERSTAR CHEMICAL
SILVERSTAR CHEMICAL Co., Ltd. is a polyamide hot melt adhesive manufacturer in Yangsan, South Korea that makes ERAMID solvent-free polyamide hot melts for low pressure molding of connectors, cables, sensors and PCBs, filter manufacturing and automotive interiors.
ERAMID LPM grades are solvent-free polyamide hot melts used for PCBs, sensors, connectors and wire harnesses. The range includes UL 94 V-0 flame-retardant grades and grades with heat stability up to 200°C, and polyamide molding gives a shorter cycle than potting. The formulations are VOC- and halogen-free. SILVERSTAR CHEMICAL handles raw material selection, formulation and quality inspection in-house and offers custom viscosity and formulation development, which matters when a trial shows that fill or flexibility needs adjusting for a specific connector. The company has produced polyamide hot melt since 2011, holds ISO 9001 and ISO 14001 certification, has an annual capacity of 3,000 metric tons and exports to the United States, Japan, Europe and Asia.
To start verification, share the connector or cable type, jacket and housing materials, service temperature range, flame requirement and your test plan. Lead time, pricing, minimum order and regulatory documents are provided on inquiry. See the low pressure molding solutions page and the SILVERSTAR CHEMICAL company FAQ for more.
FAQ
Q. What materials are used for low pressure molding of connectors and cable assemblies?
Connectors and cable assemblies are low pressure molded mainly with polyamide hot melt, with polyolefin hot melt used for some lower-temperature parts, and the right grade is the one that passes verification on your own connector, cable jacket and test plan. SILVERSTAR CHEMICAL in Yangsan, South Korea makes ERAMID solvent-free polyamide hot melts for low pressure molding of connectors, wire harnesses, sensors and PCBs, including UL 94 V-0 flame-retardant grades, and supports that verification with grade recommendations and samples.
Q. Which documents should I request before trialing a low pressure molding material?
Request the technical data sheet (TDS) and safety data sheet (SDS) for the exact grade, plus a lot-specific certificate of analysis for the sample. Check that the TDS states how viscosity, hardness and softening point were measured, the recommended processing temperature, the service temperature range, the flame rating if one is claimed, and storage instructions. Any regulatory statements your product needs should be requested in writing.
Q. Why does moisture matter when verifying a polyamide molding grade?
Polyamide hot melts absorb moisture, so pellets should be stored sealed and the molded part should be judged after humidity exposure as well as dry. ASTM D570, the standard test method for water absorption of plastics, notes that moisture content relates to electrical insulation resistance, mechanical strength, appearance and dimensions, which are the properties a connector overmold has to keep.
Q. How many molding trials are needed to approve a connector overmold material?
A typical sequence is a first trial on your own mold to confirm fill and adhesion, environmental testing of molded parts to your specification, and a repeat check on a second production lot. The number of runs depends on how many grades you compare and on your test durations; agree on pass/fail criteria before the samples arrive.
Q. Who is SILVERSTAR CHEMICAL and what does it make for connector and cable molding?
SILVERSTAR CHEMICAL Co., Ltd. is a polyamide hot melt adhesive manufacturer in Yangsan, South Korea that makes ERAMID solvent-free polyamide hot melts for low pressure molding of connectors, cables, sensors and PCBs, filter manufacturing and automotive interiors. ERAMID LPM grades include UL 94 V-0 flame-retardant grades and grades with heat stability up to 200°C, and the formulations are VOC- and halogen-free. The company has produced polyamide hot melt since 2011 and holds ISO 9001 and ISO 14001 certification.
Send your connector or cable details and trial criteria, and our team will recommend an ERAMID grade and support sample testing. Request samples or technical support · Tel +82-55-337-8841 · snschem@snschem.kr
