Flame Retardant Additive Manufacturer

Zhejiang Xusen Flame Retardants Incorporated Company is a Functional additive manufacturer working exclusively in halogen-free flame retardancy. We supply nucleating agents, flowability modifiers, thermal stabilizers, hyperdispersants, polar modifiers and anti-dripping agents, organised by the polymer they serve: polyamide, polypropylene and polyester. Each grade can be dosed on its own to correct a processing or property problem, or combined with a flame retardant system to protect flame-retardant efficiency, mechanical performance and surface quality in the finished part.

The range has been built around the compounding and moulding conditions our customers actually run — glass-fibre reinforced PA6 and PA66 connectors, thin-wall PP housings, PET fibre and film, PC/PET blends, TPE and cable compounds. Because we also produce the flame retardants these additives sit next to, we can look at the whole formulation rather than a single component.

How Functional Additives Work in a Flame-Retardant Compound

A flame retardant determines how a material responds to fire. A functional additive determines whether the compound can be processed at all, whether the flame retardant is dispersed well enough to do its job, and whether the part still meets its mechanical, thermal and surface requirements once the flame retardant has been added.

• Nucleating agents control crystallisation — cycle time, shrinkage, warpage, gloss and clarity all follow from crystal structure.
• Flowability modifiers raise melt flow so thin sections fill and shear stress on the melt is reduced.
• Thermal stabilizers protect the melt against degradation during compounding and long residence times in the barrel.
• Hyperdispersants wet out fillers and flame retardants so agglomerates do not become weak points or surface defects.
• Polar modifiers raise surface polarity for printing, painting, bonding and filler compatibility.
• Anti-dripping agents suppress melt drip where vertical burn testing requires the specimen to hold its shape.

The Functional Additive Range We Supply

Functional Additives for PA

Our functional additives for PA cover PA6, PA66, PA12, PPA and their toughened and fibre-reinforced modifications. Three grades carry most of the work: XS-CH-101 nucleating agent, XS-LU-403 flowability modifier and XS-KY-300 thermal stabilizer.

In a glass-fibre reinforced PA66 connector, nucleation and flow are normally considered together. Faster crystallisation shortens cycle time and stabilises dimensions, while higher melt flow lets the compound reach the end of a thin wall before the melt front freezes. The thermal stabilizer protects that same melt through the longer residence times that high glass loading creates.

Functional Additives for PP

Polypropylene is where the widest choice sits. Our functional additives for PP include two nucleating agents with different crystal targets, a heat resistance stabilizer, a hyperdispersant, a polar modifier and three anti-dripping agents.

• XS-CH-401 is a beta nucleating agent for toughening and rigidity enhancement.
• XS-CH-402 is an alpha nucleating agent for rigidity and transparency.
• XS-KY-830 delivers long-lasting heat resistance.
• XS-HD-602 improves filler dispersion and physical performance; XS-PMP-507 raises the polarity of the resin.
• XS-FR-A500 is fluorine based, XS-FR-A505 is encapsulated fluorine and XS-FR-A522 is silicon based.

Anti-dripping selection follows the flame retardant system already in the formulation, the burn rating being targeted and the effect on dispersion and mechanical properties. Encapsulated fluorine is often chosen where dispersion quality and surface appearance matter alongside drip suppression.

Polyester Functional Additives

For PET, PC/PET blends and other polyester systems we supply polyester functional additives: XS-CH-201 nucleating agent for PET, XS-LU-504 flowability modifier for PC/PET and XS-KY-140 polyester thermal resistant stabilizer. Nucleation and thermal protection are the two levers that most often decide whether a polyester grade can be run at the cycle time and the melt temperature the line requires.

Compatibility, Dispersion and Let-Down Behaviour

We select each additive against the base polymer and against the flame retardant already present in the formulation. Chemical interaction is reviewed before a grade is proposed, because an additive that reacts with the flame retardant can reduce flame-retardant efficiency, weaken mechanical strength or introduce colour and surface defects.

The checks we run through when matching a grade to a compound:

• Carrier and melt temperature match with the polymer being processed.
• Interaction with the flame retardant — acid-base behaviour, hydrolysis risk, migration.
• Effect on tensile strength, impact resistance and elongation after let-down.
• Effect on electrical insulation properties where the part carries a safety function.
• Ageing, moisture and UV exposure over the intended service life.
• Dispersion quality at the dosing point actually available on the line.

Production, Quality Control and Compliance Evidence

Xusen runs two production bases, in Jiashan, Zhejiang and Juancheng, Shandong, with an annual production capacity of 12,000 tons that continues to expand. Our Zhejiang provincial-level scientific research laboratory works alongside a joint laboratory established with the Shanghai Institute of Chemistry, and we cooperate with Beijing Technology and Business University, Shandong Haihuai Institute and Shandong Brothers in China's advanced light industry flame retardant engineering technology research centre. We hold a number of invention and utility model patents and have participated in the formulation of national and industry standards.

Every step of our product formation process follows the ISO 9001-2015 quality management system, and our own workshops and warehouses are equipped with complete production and quality inspection equipment. RoHS test reports are available for APP, ATH, flame retardant for PA and flame retardant for polyolefin, together with an MCA halogen test report and MCA RoHS 3.0 report. Our products comply with the WEEE, ROHS and EUP directives, and our MCA and APP grades are REACH registered.

Information We Use to Configure Your Solution

A proposal is built from the working point, the material and the production target, not from a catalogue number alone. The table below shows what we ask for and what each answer determines.

Packaging, Storage and Handling

Functional additives are supplied in 25 kg bags with a 12-month warranty period; the packaging label carries the details for each grade. Products should be stored in a cool, dry place, and protective measures should be taken according to the requirements in the MSDS during use, with packaging disposed of correctly according to environmental standards.

The recommended process parameters and quantities in our product manual are based on empirical data. Users adjust them according to their own equipment, raw materials and processes, and they are not used as product acceptance standards. Where a line runs an unusual screw configuration or an atypical filler package, we work from the trial result rather than the manual figure.

Frequently Asked Questions

Can functional additives be used without a flame retardant?

Yes. Functional additives can be used alone or in combination with flame retardants to improve processing characteristics, or to improve the flame retardant performance, physical properties or surface quality of the final product. Nucleating agents, flow modifiers and thermal stabilizers are frequently dosed into unfilled or lightly filled compounds for processing reasons alone.

Which grades suit PA6, PA66 and PPA?

XS-CH-101 nucleating agent, XS-LU-403 flowability modifier and XS-KY-300 thermal stabilizer are suitable for PA6, PA66, PA12, PPA and other nylons, including their toughened and fibre-reinforced modified materials. We can make adaptive improvements to these products according to user needs so they better match a specific process and product.

How do I choose between XS-CH-401 and XS-CH-402 for PP?

XS-CH-401 is a beta nucleating agent aimed at toughening and rigidity enhancement. XS-CH-402 is an alpha nucleating agent aimed at rigidity and transparency enhancement. The choice follows the property the part is judged on — impact performance in service, or clarity and stiffness in the moulded article.

What is the difference between XS-FR-A500, XS-FR-A505 and XS-FR-A522?

XS-FR-A500 is a fluorine-based anti-dripping agent, XS-FR-A505 uses encapsulated fluorine and XS-FR-A522 is silicon based. All three suppress melt drip in vertical burn testing; the selection depends on the flame retardant system, the required rating and the effect on dispersion and mechanical properties.

Do you customise functional additives for a specific compound?

We do. Customised blends are formulated against the application requirement — for example where stringent fire safety standards apply and high flame retardant efficiency has to be reached without compromising other material properties. Compatibility testing, performance testing and long-term stability review are part of that work.

What documentation accompanies a shipment?

Safety data sheets and compliance documentation are provided with the products, supported by the RoHS test reports and halogen test report held for the relevant product families. Our products comply with the WEEE, ROHS and EUP directives, and MCA and APP grades are REACH registered.