Exporters of footwear, flooring, toys, packaging and automotive parts face the same pressure: buyers want products with less odor, fewer chemical residues and a clear path through market-access checks. Foamed parts are a particular concern because the foaming agent decomposes inside the product and leaves gases and solid by-products behind.
Three terms are often mixed up: low VOC, low formamide and low ammonia. They are different measurements, and a supplier claim on one does not automatically cover the others. The real question for a buyer is how to pick a chemical foaming agent that fits the target market, passes finished-product testing and still runs well in your process. This guide walks through that evaluation step by step.
Three ideas are easy to confuse:
A good result on the raw material does not guarantee a good result on the final article. Resin, additives, processing temperature, cooling and storage time all influence emission. For that reason, choose the test method according to the target market and product category, and test the finished part. Examples of methods used in practice include ISO 16000-9 (emission test chamber) and ISO 16000-6 (sampling and analysis of VOCs) for indoor-related materials, but your customer or market may require a different one.
Some ADC (azodicarbonamide) foaming systems can form formamide and ammonia as part of the decomposition process. Consumer goods such as footwear and children's products often need these residues evaluated with extra care. Formamide appears on the ECHA REACH Candidate List of substances of very high concern, which is one reason brands set their own limits.
It also helps to separate two approaches:
Both can meet a requirement, but they need different proof and different process work.
Start with three facts: the destination country or region, the final product category and the regulations that apply to that category. There is no single VOC or formamide limit that fits every export product. A shoe sole, a toy, a floor covering and an automotive trim part can each fall under different rules.
Then separate the three kinds of requirement:
For children's products, indoor materials and other sensitive uses, confirm restricted-substance requirements early, before you lock in a formulation. Regulations and test methods are revised from time to time, so check the current version.
Write the pass/fail rules down before you compare suppliers. At a minimum, record:
Important: do not assume one VOC or formamide limit applies to every export product. The requirement depends on the destination, the product type and the specific regulation or customer standard.
A clean residue profile is only useful if the grade also foams properly. Joysun's technical information lists decomposition temperature, gas yield, residue characteristics and cell structure as the main selection parameters, and they should be read together.
Compare the decomposition temperature with the actual processing window of your resin. A grade that decomposes too early loses gas before pressure can hold the cells; one that decomposes too late leaves the melt too stiff to expand, so foaming is weak or cells collapse. Activators such as zinc compounds can lower the effective decomposition point of an ADC system, so the formulation matters as much as the grade.
The temperature on a data sheet is only a guide. Confirm compatibility with real processing trials, watching for premature foaming, under-foaming and cell collapse.
Gas yield, in mL/g, shows how much gas the agent releases per gram. A higher yield can reach the same density at a lower dosage, which may reduce the residue load and the material cost. For example, Joysun lists standard ADC at 220 mL/g and OBSH at 140 mL/g on its synthesis and custom masterbatch page, so OBSH needs a different loading.
Avoid choosing on gas yield alone. A high-yield grade can still give poor cells or the wrong surface if its decomposition behavior does not fit your process.
Evaluate the foamed part, not only the powder. Measure cell uniformity, finished density, dimensional change and surface appearance. The emphasis differs by product:
The first route keeps ADC chemistry and controls the by-products through formulation. Joysun's low-VOC, low-formamide, low-ammonia ADC foaming agents include two grades listed for EVA compression-molded midsoles:
When evaluating this route, ask three questions: can the current formulation keep running, does the process need adjusting, and do the test results meet your customer's acceptance criteria?
The second route changes the chemistry. OBSH (4,4'-oxybis(benzenesulfonyl hydrazide)) can replace ADC in some applications. Joysun states that its decomposition products are free of ammonia and formamide. Its decomposition temperature is 160°C and its gas yield is 140 mL/g, according to the same page.
Because OBSH differs from ADC in gas yield and temperature, look beyond the environmental claim. Review dosage, processing temperature, resin compatibility and cost change at the same time.
| Evaluation factor | Low-residue ADC | OBSH-based system |
|---|---|---|
| Residue profile | Requires verification of relevant residues | Does not generate formamide or ammonia as decomposition products |
| Gas yield | Depends on grade | Depends on grade; may be lower than ADC |
| Processing compatibility | Check existing formulation and process | Validate decomposition temperature and resin compatibility |
| Key decision | Whether residue limits can be met | Whether alternative chemistry meets both compliance and performance needs |
This is a general technical comparison. Specific results depend on the product data sheet and on your own tests.
Ask every supplier for the technical data sheet (TDS) and safety data sheet (SDS). Check decomposition temperature, gas yield, chemical composition and storage requirements. Compare the batch and the document version, and confirm that the quality documents cover the specific substances your buyer restricts.
Test the article rather than relying only on a raw-material certificate, because processing conditions affect the final residue levels.
A certificate or a "low-VOC" label tells you little about whether the supplier can support you over many shipments. Compare these five areas:
Joysun makes foaming agent active ingredients through its own synthesis, not only by formulating bought-in material. Its range covers ADC, OBSH, TSH, TSSC, H/DPT and two activators (ZBS and ZTS), plus custom pre-dispersed masterbatch in a carrier resin matched to your polymer. A masterbatch removes dust handling and improves dosing precision. Custom particle size for ADC is also available, for example coarser for dry blending or finer for masterbatch production.
Zhejiang Joysun Advanced Material Co., Ltd. was established in 2005 and is based in Pinghu, Zhejiang. It reports ISO 9001 certification, AEO Advanced Certification from Chinese customs (2025), national High-Tech Enterprise status and more than 600 clients worldwide. Application support comes from its R&D center. More background is on the about us page.
Need a low-residue foaming solution for an export project? Share your resin, process and target market, and Joysun's technical team can suggest suitable grades. Browse the full product list or contact the sales team at sale@joysunsh.com for data sheets and samples. Related lines include PVC Ca-Zn stabilizers and PVC flame retardants for projects that need a full additive package.
