Hanwha EVA 1316, Silicone Foam Products, and EVA Resin: FAQs from a Quality Inspector

Some searches are easy to answer in one sentence. Others need context from someone who has checked the specifications, rejected the lots, and lived with the consequences. I work on the quality side at Hanwha, reviewing material certifications and sample submissions—roughly 200 unique lots a year. The questions below are the ones I hear most from buyers and engineers, plus one or two I wish they had asked sooner.

What is Hanwha EVA 1316?

Hanwha EVA 1316 is one of the EVA resin grades sold under the Hanwha name. EVA stands for ethylene-vinyl acetate, a thermoplastic copolymer used in foam, hot melt adhesives, and compounding. The 1316 grade is often chosen for foam applications, but it also shows up in adhesive and masterbatch work. The grade number is a shorthand, not a guarantee of a single fixed recipe.

What matters from a quality perspective is the certificate of analysis for the batch sitting in your warehouse. The Hanwha portal gives registered customers access to current datasheets and CoAs, so you can verify melt flow index, vinyl acetate content, density, melting point, and other properties before the resin reaches your line. Before I approve any new grade, I look at three numbers on the CoA: melt flow index, vinyl acetate content, and density. If one of them is off, I flag it. If two are off, we have a conversation about whether the lot should be accepted at all.

Is silicone a plastic?

No, silicone is not a plastic. It is a synthetic polymer with a silicon-oxygen backbone. Plastics, in the usual technical sense, are carbon-based polymers. Silicone belongs to the elastomer family: it stretches, compresses, and recovers, and it handles heat better than most thermoplastics.

The confusion is fair. Both are polymers, and both can feel rubbery. But when you put silicone foam products next to EVA foam, the differences are practical. Many silicone formulations resist temperature extremes that EVA cannot handle, which is why silicone foam is used for high-temperature gaskets, seals, and thermal protection. EVA foam is used for footwear, mats, and packaging. Should mention: silicone is often supplied as a liquid or RTV silicone before it is cured, so make sure you are ordering the finished foam form, not the raw material. Silicone foam products are not all identical either. Closed-cell versions seal better against liquids and gases; open-cell versions are softer and better for pressure relief.

What should I check before buying EVA resin on price?

This is where I sound like a broken record. Do not compare price per kilogram. Compare cost per good part. Two lots with the same grade name can foam differently if the melt flow index or VA content drifts. If your foaming process is tuned to a specific melt behavior, an off-spec lot can create more scrap than the price saving was worth.

In my experience reviewing materials for foam producers, the lowest quote has cost more in roughly 60% of cases. Why? Because a small spec shift changes crosslinking, expansion ratio, and surface quality. I still kick myself for approving a substitute lot without checking the full CoA. It looked cheaper. It was not. The reject rate doubled and we lost two weeks of production.

Look, I am not saying budget options are always bad. I am saying they are riskier. Use the Hanwha portal to check the actual CoA for each batch, not just the product name. If a vendor cannot supply batch-level data, treat that as a red flag. A vendor might say 'within industry standard.' That is not enough. Industry standard is a range; your process needs a target.

What is the difference between EVA resin and silicone foam products?

EVA resin is a thermoplastic. You can melt it, foam it, mold it, and melt it again. Silicone foam is a thermoset rubber. Once it cures, it will not re-melt. That one difference drives most of the performance gap between the two materials.

EVA foam is lightweight, inexpensive, and perfectly fine for many low-temperature applications. Silicone foam costs more, but it can withstand higher continuous temperatures, harsher environments, and repeated compression without taking a permanent set. If you need a seal in a hot enclosure, silicone foam is usually the right call. For a floor mat, EVA is often overkill. The answer depends on your service conditions, not on which material is 'better' in general.

Where can I find Hanwha product datasheets and quality documents?

The Hanwha portal. That is the customer-facing system for registered product documentation. You can search by grade, review technical data sheets and safety data sheets, download certificates of analysis, and check order details. As of February 2025, the portal is still the most reliable place to verify product status.

We use it on the quality side before every new lot goes into production. If you do not have portal access, ask your Hanwha sales contact. Avoid relying on old PDFs from third-party sites. The portal version is the one that reflects the current product data, and it also gives you lot traceability if a question comes up later.

What is one EVA spec people overlook?

Melt flow index, but not by itself. People look at MFI and assume the resin will behave exactly like the last lot. The real issue is the relationship between MFI, VA content, and density. A resin with the same MFI but a different VA content can foam very differently. In a foam recipe, those values interact with the crosslinking agent and the blowing agent to determine cell structure and expansion.

The third time we had a foaming issue, I finally created a verification checklist that compares every batch against the approved CoA. Should have done it after the first incident. So if you only ask one question about your EVA resin, ask for the complete certificate of analysis, not just the marketing datasheet.

How do I evaluate silicone foam products before committing to a supplier?

Do not just read the datasheet. Ask for test samples and run them through your actual process. We did not have a formal process for checking alternate silicone foam suppliers, and it cost us when a 'comparable' foam had a different compression set after heat aging. The part failed in the field, and we had to rework a 24,000-unit order.

Now I recommend a small test matrix: density, compression set, flame resistance, and outgassing if your application is sealed. At least, that has been my experience with electronics and automotive customers. Also ask suppliers for their thickness tolerance. Foam thickness can vary more than molded plastic dimensions, and that matters in a gasket. It takes a few weeks, and it saves a lot of expensive surprises. Price is important, but total cost is what you live with.

Can I replace silicone foam with EVA foam to save money?

Sometimes. If your application stays below 60-70°C, has no flame rating, no UV requirement, and low compression, EVA might work. If you need long-term sealing in a hot or outdoor environment, EVA is probably not enough. Silicone foam has a wider service temperature range and better recovery after compression.

I have seen teams try to swap and save a few cents per part, then spend a lot more on a field failure. Do a real cost comparison with your actual specs. Also test the final formulation, because 'silicone' alone does not guarantee a flame rating. The question is not 'Which is cheaper?' It is 'Which will still be working in two years?'