How to Change Food Grade Standards of Nylon Rods and Sheets?

Introduction

In recent years, the safety and compliance of food-grade plastic materials have become the focus of global manufacturing. As a widely used nylon material in the industrial field, changes in its food-grade certification directly affect key industries such as food processing machinery and packaging equipment. In 2023, DuPont announced that its classic nylon resin Zytel 42 will no longer hold FDA food-grade certification, and will instead launch a high-priced alternative Zytel 42FG. This change has caused a shock in the industry and prompted practitioners to re-examine the food-grade standards and alternatives for nylon rods and sheets. This article will analyze from six dimensions, including technical standards, market strategies, and alternative materials, to provide scientific response suggestions for the industry.

Technical core of food-grade nylon certification standards

The food-grade compliance of nylon materials must meet the FDA 21 CFR 177.1500 standard, which requires that the material does not release harmful substances when in contact with food and is resistant to high temperature, grease and other environments. As a representative product of nylon 6/6, Zytel 42 has long passed migration tests (total migration ≤ 10mg/dm²) and sensory tests (no odor, no color migration), becoming the first choice for food machinery parts (FDA Food Contact Substance Database). However, after DuPont adjusted the formula this time, although Zytel 42FG claimed that its performance remained unchanged, it needed to resubmit a full set of test reports, resulting in an extension of the certification cycle and a surge in costs. This change reveals that food-grade certification is not only dependent on material composition, but is also closely related to the manufacturer’s compliance investment.

The “formula game” dispute between Zytel 42 and 42FG

DuPont claims that Zytel 42FG is an “optimized version”, but according to comparative tests in industry laboratories, the difference between the two in key indicators such as tensile strength (80MPa vs 82MPa) and melting point (260℃ vs 262℃) is less than 2%. It is worth noting that the price of 42FG has increased by 35%-50% compared with the old model, while the production process has simplified the types of additives. Industry experts pointed out that this move may be to achieve a premium through “certification reset” rather than a substantial technological upgrade. Although this strategy creates profit growth points for enterprises, it increases the supply chain risks of downstream manufacturers.

The market truth about the demand for food-grade nylon

Although nylon has significant advantages in wear resistance and mechanical strength, the food field is not its main battlefield. According to statistics, in the global food-grade plastic market in 2022, polyethylene (PE) accounts for 38%, polypropylene (PP) accounts for 29%, and nylon series accounts for only 7%. User surveys show that engineers choose nylon mostly because of its anti-fatigue properties (gear applications) or high temperature resistance (baking equipment), rather than actively pursuing food-grade certification. This explains why the revocation of Zytel 42’s certification did not trigger a large-scale replacement trend, but it also warns manufacturers to accurately locate demand.

Diversified selection of compliant alternative materials

In the face of certification changes, the industry can turn to the following compliance solutions:

1. Nylon 12 (PA12): Passed ISO 10993 biocompatibility certification, especially suitable for long-term contact with acidic food environments
2. Polyoxymethylene copolymer (POM): Meets EU 10/2011 standards, comparable to nylon 6/6 in wear resistance and dimensional stability
3. Ultra-high molecular weight polyethylene (UHMW-PE): FDA certified and lower cost, suitable for conveyor belts, guide rails and other scenarios

Emergency strategies and cost control of the supply chain

1. Inventory buffer: It is recommended that companies establish a 3-6 month Zytel 42 safety inventory and use the transition period to complete the material switch
2. Dual source procurement: Simultaneously evaluate Cast Nylon (cast nylon) supplier, its large-size sheets (such as 12″x12″x48″) have been certified by NSF
3. Process optimization: Improve the compliance of non-certified nylon through surface coating technology (such as food-grade silicone treatment)

Industry enlightenment of food-grade certification changes

This incident exposed three deep-seated problems:

1. Certification dependency risk: Changes in a single material certification can impact the entire supply chain
2. Lack of technical transparency: Manufacturers do not fully disclose the physical and chemical basis for formula adjustments
3. Lagged development of alternative materials: The industry has insufficient investment in research on nylon substitutes

The International Plastics Association (SPI) recommends the establishment of a Material Certification Database Alliance to achieve test data sharing and reduce the cost of repeated certification for enterprises.

Conclusion

The adjustment of DuPont Zytel series certification is both a challenge and an opportunity to promote industry upgrading. Practitioners are advised to:

1. Re-evaluate the necessity of nylon in food applications and give priority to economical alternatives such as UHMW-PE
2. Require suppliers to provide complete migration test reports instead of relying solely on certification labels
3. Participate in industry associations to promote transparency in certification standards

With the new EU (EU) 2023/15 regulations and FDA guidance updates, the compliance threshold for food-grade materials will continue to increase. Only through technological innovation and supply chain collaboration can we seize the initiative in change.