Three Product Lines in the Flame Retardant Series: PE Film, Transparent Polyester and Synergist Replacement

The first thing to confirm when selecting a flame retardant is not the price, but the substrate and finished article form: for PE film, transparent polyester parts and systems requiring replacement of antimony trioxide, the applicable additive types are completely different. Californium Curium’s flame retardant series is divided into several lines by substrate; in the documentation, each model has its own dedicated main body page. This article summarises the composition, dosage, processing temperature, packaging and shelf life of each model in tables and clarifies a point that is easily confused: "low-halogen" does not mean "halogen-free".

1Series Composition and External Publication List

1

The flame retardant series catalogue in the functional additives documentation lists: R911 (halogen-free flame retardant for PE), R912 (transparent halogen-free flame retardant), R915 (transparent halogen-free flame retardant specifically for PET/PETG), R940 (reactive flame retardant for unsaturated acrylic-polyurethane systems), R218 (flame retardant synergist, partial replacement for antimony trioxide), and 63# brominated flame retardant (halogenated flame retardant for PE/PP high-temperature plastic extrusion coating cast film). (Source: Californium Curium – Functional Additives 1.09 PDF, page 3 (printed page 55) and page 4 (printed page 83) product catalogue)

External publication list: The models in this series published on this website are R911, R912, R912B, R915, R940 and R218, 6 in total (the series page is consistent with the public product data interface). The catalogue footnote states that "products in grey type have been discontinued"; the 63# entry is not in grey type in the catalogue, but it is a halogenated product. In line with the official website's practice of publishing only models that can be checked item by item and conform to their positioning, it is not included in the publication list. Whether 63# is still on sale or requires a separate page is not stated in the documentation. (Source: same as above; the original catalogue footnote appears on pages 3-4 of the 1.09 PDF)

2PE Thin-Gauge Article Line: R911 (and Its Masterbatch Version M911)

2

Positioning: A halogen-free flame retardant specifically developed for thin-gauge polyethylene (PE) articles (film, thin sheet, woven yarn, ultra-thin pipe, etc.). (Source: Flame Retardant Series PDF, page 1, printed -49-)

PE Thin-Gauge …

Item	Content from the documentation (key points as recorded)
Core composition	Hindered amine compound based on tetramethylpiperidine derivatives; free of halogens (chlorine, bromine, etc.), compliant with RoHS and REACH
Flame retardant mechanism	Interrupts combustion by capturing free radicals generated during burning and inhibiting the chain reaction; it also provides some antioxidant effect and retards ageing of PE materials
Synergistic dispersant	A small amount of non-ionic surfactant helps the hindered amine disperse uniformly in the PE melt, avoiding agglomeration without affecting processing flowability
Dosage and rating	At a dosage of 10%-20%, thin-gauge PE articles can achieve UL94 V-2 rating (film category) or FV-2 rating under GB/T 2408-2008 (adjusted according to thickness)
Processing temperature	150-200℃ (consistent with conventional PE film processing); avoid excessively high temperatures that cause the flame retardant to decompose
Scope of application	Various PE films (packaging film, shrink film, protective film, agricultural mulch film); PE thin sheet and ultra-thin articles (electronic insulating sheet, lightweight packaging sheet)
Storage	Store in a cool, dry and ventilated place, avoid moisture and direct sunlight; shelf life 12 months; keep sealed after opening
Packaging	25 kg bag, double-layer PE bag

(Source: Flame Retardant Series PDF, page 1, printed -49-; identical text in Californium Curium – Functional Additives 1.09 PDF, page 53)

Masterbatch counterpart M911 (PE halogen-free flame retardant masterbatch): compounded from hindered amine flame retardant + hindered amine light stabiliser + LLDPE resin and pelletised; recommended addition ratio 10%-25%; processing temperature <250℃; in the documentation indicator table, the flame retardant effect row is UL94 V1; specific gravity 0.89g/cm³; melt flow rate 6.9g/10min. The precautions in the documentation state that the formulation should preferably not be combined with flammable or combustion-supporting components (such as wax, ester, aluminium oxide), should not be used with anti-drip agents, and is not suitable for fibre reinforcement; if unavoidable, conduct a trial first to confirm. (Source: Californium Curium – Functional Masterbatch 1.05-4 PDF, page 5, printed -1-)

3Transparent Polyester Line: Division of Roles Among R912 / R912B / R915

Outer bar = total amount, inner bar = a part of it; the difference between the two = the rest, the right end marks the remaining amount.

Total… ≤ 1500 ppmSubitemBr + Cl ≤ 900 ppmUnit unified as ppm · Nested bars only express inclusion relationship; detection scope of two limit values follows source text, no conversion performed.Bar length indicates inclusion relationship, two bars are not additive

• … ≤ 1500 ppm
• Br + Cl ≤ 900 ppm
• Unit unified as ppm · Nested bars only express inclusion relationship; detection scope of two limit values follows source text, no conversion performed.
• Bar length indicates inclusion relationship, two bars are not additive

• Total halogens1500 ppm
• Br + Cl900 ppm

Chart data (source text verbatim)

Level	Limit
Total halogens	≤ 1500 ppm
Br + Cl	≤ 900 ppm

Source textScale 0–1500 ppm

Scale = criterion limit (unit ppm); the side marked in red = exceedance direction; values are taken directly from source criteria.

Both tiers satisfiedNeither tier satisfied025050075010001250ppmBr+Cl ＜ 900 ppm…Fig. Halogen-free criterion ppm red line← Lower value means more "halogen-free"; dashed line = red line from source, segment = judgment interval cut by red lineClaim permitted only below the red line: Halogen-free threshold

• Br+Cl ＜ 900 ppm
• Fig. Halogen-free criterion ppm red line
• ← Lower value means more "halogen-free"; dashed line = red line from source, segment = judgment interval cut by red line
• Claim permitted only below the red line:

• Br+Cl＜ 900 ppm

Chart data (source text verbatim)

Criterion	Limit	Description
Br+Cl	＜ 900 ppm	Criterion: Br+Cl 900 ppm

Main text criteria layerScale 0–900 ppm

All 3 models target transparent polyester systems, but the input conditions differ. The key parameters given in the documentation are as follows (as recorded):

Transparent Po…

Item	R912	R912B	R915
Applicable substrate	PET, PETG, TPU	PET (fibre, film, sheet)	PET, PETG (high transparency)
Main composition	tris(lithium dimethylbenzene carbonate) phosphate (new organophosphorus lithium salt flame retardant system), white crystalline powder	phosphorus-based main component + a small amount of nitrogen-based synergist + non-ionic dispersing additive	polyol phosphate ester (additive-type organophosphorus system, free of halogens and heavy metals)
Key indicators	Effective flame retardant content ≥98.0%; phosphorus content ≥9.8%; decomposition temperature ≥285℃; bulk density 0.87-0.93 g/cm³; moisture ≤0.15%; volatile matter (120℃/2h) ≤0.5%	— (the documentation focuses mainly on mechanism and performance description)	Phosphorus content 18%; melting point 210℃; halogen content not detected (IEC 61249-2-21); onset temperature of thermal decomposition ≥260℃; moisture ≤0.2%; fineness (325 mesh pass rate) ≥98%
Flame retardant rating and dosage	TPU 2%-7% (polyester type 2-4%, polyether type 5-7%); PETG 1.5%-3%; PET 1.5%-3%	At a dosage of 1.5%-5%, UL94 V-0 can be achieved; limiting oxygen index (LOI) increases to above 38%	UL94 V-2 (1.5mm): 1%-2%; UL94 V-0 (1.0-1.5mm): 2%-4%
Transparency position	The effect on material transparency is controllable: substrate light transmittance decreases by about 20%, suitable for semi-transparent and low-transparency flame retardant modification scenarios	Not applicable (focused on V-0 and mechanical property retention)	No negative effect on substrate light transmittance or haze; no whitening, no yellowing and no exudation during processing
Processing temperature	Suitable for conventional extrusion, injection moulding and pelletising processes: PET 230-280℃, PETG 190-250℃, TPU 160-225℃	Recommended 230℃-280℃ (20-30℃ lower than conventional PET processing temperature)	Extrusion/injection moulding barrel 240-275℃; die/mould 60-90℃; prolonged residence above 290℃ is prohibited
Packaging	25kg/bag (inner thickened PE moisture-proof bag + outer wear-resistant woven bag)	25 kg bag, double-layer PE bag	25kg composite woven bag with inner PE film liner
Shelf life	12 months when sealed and stored at room temperature	12 months	12 months

(Source: Californium Curium – Flame Retardant Series PDF, pages 2-3 (-50-/-51-) for R912; page 4 (-52-) for R912B; pages 5-6 (-53-/-54-) for R915; Californium Curium – Functional Additives 1.09, pages 54-58 contain the same text; the complete physical and chemical indicators table for R912B is not provided in the documentation (this item is not listed), and only the mechanism and performance description is currently available.)

A usage boundary for R912: The documentation states that this product is a dripping-type flame retardant; when "non-dripping" is required, it can only be used in combination as a flame retardant synergist. It can be compounded with charring agents and anti-drip additives to improve the V0 pass rate and anti-drip effect. (Source: Flame Retardant Series PDF, page 3, printed -51-)

Mixing and process points for R915 (as recorded): Raw material drying — dry PET/PETG substrate at 120℃ for 4-6h in advance to moisture ≤0.03%, preventing hydrolysis whitening during processing; pre-mixing — high-speed mix R915 with pellets for 5-8min; screw selection — select a low-shear polyester-specific screw to avoid excessive shear causing reduced light transmission; masterbatch preparation — a 20%-30% concentration PET/PETG flame retardant masterbatch can be prepared first for more convenient use and better dispersion. The documentation also notes that this product is an additive-type flame retardant and does not participate in the polyester copolymerisation reaction; for articles of different thicknesses, equipment and process conditions, and synergistic systems, the dosage may be adjusted slightly. Customers are advised to carry out small-scale trials in advance to determine the optimum formulation. (Source: Flame Retardant Series PDF, page 6, printed -54-)

Compliance position of R915 (as recorded): Meets the IEC 61249 halogen-free standard (Br+Cl <900ppm, total halogens <1500ppm); RoHS 2.0 (free of lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls, polybrominated diphenyl ethers); REACH (free of SVHC substances of very high concern); combustion behaviour is halogen-free and low-smoke, and does not produce toxic products such as dioxins. (Source: same as above)

4Reactive series: R940 (UV acrylic and polyurethane systems)

simple physical blending without participating in the reaction is not recommended

Product composition (mass fraction, as recorded):

(Source: Flame Retardant Series PDF, page 7, printed -55-)

Processing and dosage (as recorded): For UV acrylic systems (photocuring), the recommended dosage is 15-30% (based on total resin mass); directly mix uniformly with acrylic monomers, prepolymers and photoinitiator at room temperature, deaerate, then UV-cure. It is recommended that the total phosphorus content of the system be controlled at 1.5-3.0%, which can achieve a UL94 V-0 flame retardant rating. For polyurethane systems (PU/PUA), the recommended dosage is 12-25% (based on the polyol component); it can be mixed directly with the polyol and then reacted with isocyanate. Note that the NCO/OH ratio should be controlled: R940 contains hydroxyl groups and will consume NCO groups, so the isocyanate dosage in the formulation needs to be adjusted. (Source: Flame Retardant Series PDF, page 8, printed -56-)

addition-cure silicone (platinum-catalysed) systems pose a toxicity risk

5Synergistic substitute series: R218 (replacement for antimony trioxide)

R218 plays the role of “antimony saving”: partially replacing antimony trioxide in halogenated flame retardant formulations while also providing smoke suppression and char formation. Key points from the document (as recorded):

(Source: Flame Retardant Series PDF, page 9, printed -57-; Californium Curium – Functional Additives 1.09 PDF, page 61, same text)

6A statement that is easy to confuse: low-halogen ≠ halogen-free

Moved from the bodyComponents and content · full table

Item	Content
Category and composition	Environmentally friendly phosphorus-silicon flame retardant; main component is aluminium phosphosilicate, chemical formula Al(SiO₂)PO₄·2H₂O
Appearance and morphology	White crystalline powder, odourless and non-toxic; fibrous or needle-like under microscope, with a fine and loose texture
Physical and chemical properties	Density approx. 2.6–3.2 g/cm³; melting point typically 1300–1600℃; pH value 6.5-7; slightly soluble in water and common organic solvents
Replacement position	PP/PE flame retardant systems: can replace 50% to 70% of antimony trioxide at a 1:1 ratio, and the flame retardant effect is better than that of antimony trioxide combined solely with a brominated flame retardant; PVC flame retardant systems: can 100% replace antimony trioxide
Use in halogen-free systems	Combined with phosphorus-based and intumescent flame retardants, it provides rapid char formation, oxygen barrier and smoke suppression
Applicable polymers	PE, PP, PVC, ABS, PBT, PET, etc.
Compliance	Complies with EU 2002/95/EC, REACH and other environmental regulations
Packaging and storage	Woven bags with inner polyethylene plastic bags, net weight 25kg per bag (customisable); store in a dry, ventilated warehouse away from fire, heat sources and strong oxidising agents; shelf life generally 2 years

low halogen content, no antimony, light specific gravity, no exudation, low smoke emission and low mould corrosion

When reading this entry, note that M922 is accurately positioned as “low-halogen” — its compounded system contains bromine and is not the same as the halogen-free models R911 / R912 / R912B / R915 / R940 / M911 / M915 / M918 / M933. In external communication, “低卤” should be written as low-halogen, not halogen-free. (Source: same as above; for the list of halogen-free masterbatch models, see Californium Curium – Functional Masterbatch 1.05-4 PDF, page 3, product introduction)

7Selection and use: confirm three things first

1. 01Substrate and finished-article thickness — for the same V-2 rating, the dosage ranges differ between film and thick-walled parts; R911 states clearly that “the thinner the article, the more the dosage should be appropriately increased”. (Source: Flame Retardant Series PDF, page 1 (-49-))
2. 02Processing temperature window — transparent polyester systems are sensitive to prolonged residence at high temperature: R915 must not be held above 290℃ for long periods; R912B is recommended to be processed at 20-30℃ lower than the conventional PET processing temperature; R911 should be controlled at 150-200℃. (Source: Flame Retardant Series PDF, page 6 (-54-) / page 4 (-52-) / page 1 (-49-))
3. 03Whether a synergist is needed — when it is necessary to reduce formulation cost or improve char formation/smoke suppression, consider R218; when “non-dripping” is required, dripping-type models can only be used as synergists in combination. (Source: Flame Retardant Series PDF, page 9 (-57-) / page 3 (-51-))

The document repeats the same reminder for several models: customers are advised to carry out small-scale trials in advance, and samples and process conditions should be confirmed with the technical side. On the functional masterbatch side, there are three additional general requirements for trial use: before trials, the materials need drying (PET, PA6 at 100℃ for 5 hours; PETG, PU, polyester-type TPU at 80℃ for 5 hours; polyether-type TPU at 60℃ for 5 hours); the processing temperature must not exceed the maximum recommended temperature in the product introduction sheet; the addition ratio is an internal addition (in-plastic addition) ratio (e.g. 5% masterbatch = 95% raw material + 5% masterbatch). (Source: Californium Curium – Functional Masterbatch 1.05-4 PDF, page 4, friendly reminder)

8Frequently asked questions (FAQ)

Q2: If both transparency and V-0 are required, should R912 or R915 be selected? A: It depends on the substrate and transparency requirements: R915 is intended for high-transparency PET/PETG (the document states no adverse effect on light transmittance and haze); R912 is suitable for PET/PETG/TPU, and the document states that light transmittance decreases by about 20%, making it suitable for semi-transparent and low-transmittance applications. (Source: Flame Retardant Series PDF, page 5 (-53-) / page 2 (-50-))

Q3: Both R912B and R915 are used in PET; how should they be distinguished? A: R912B targets V-0 and LOI (1.5%-5% achieves V-0, LOI ≥38%, with emphasis on mechanical property retention in fibre/film/sheet); R915 targets high transparency retention (V-2 at 1%-2%, V-0 at 2%-4%, and must not be held above 290℃ for long periods). (Source: Flame Retardant Series PDF, page 4 (-52-) / page 6 (-54-))

Q4: How is R940 added in UV systems? A: Recommended dosage 15-30% (based on total resin mass); mix at room temperature, deaerate, then UV-cure; control the total phosphorus content of the system at 1.5-3.0%; note that it must not be used together with strongly alkaline substances, and the system temperature should not exceed 120℃ for a long time. (Source: Flame Retardant Series PDF, page 8 (-56-))

Q5: How much antimony trioxide can be saved? A: In PP/PE systems, 50% to 70% can be replaced at a 1:1 ratio; in PVC systems, 100% replacement is possible (R218). (Source: Flame Retardant Series PDF, page 9 (-57-))

Q6: Are there any third-party test reports or certification numbers? A: All data in this article come from the document itself; no third-party test report numbers are attached in the document. The compliance positions that can be cited from the document are: R911 complies with RoHS and REACH requirements; R915 meets IEC 61249, RoHS 2.0 and REACH positions; R218 complies with 2002/95/EC and REACH; M922 complies with ROHS standards. (Source: the main body page of each model, see Section 9) The third-party test report numbers corresponding to the models, if any, are not listed in this item and separate test reports can be supplemented.

items that cannot be verified item by item are not published on the public product pages

Q8: How should masterbatch and additives be selected? A: These are two different supply forms: if you want to adjust the formulation yourself, select additives (R911/R912B/R915, etc.); if you want to feed directly to the machine and reduce batching steps, select masterbatch (for example, M933: PP halogen-free V0 flame retardant masterbatch, reference dosage 15-25%; in 0.4mm thick PP sheet, adding 25 parts gives non-dripping non-flammable cotton). (Source: Californium Curium – Functional Masterbatch 1.05-4 PDF, page 14 (-10-))

9Sources (verifiable item by item)

#	Source document	PDF physical page	Printed page	Used in section(s)
1	Flame Retardant Series.pdf	Page 1	-49-	Sections 1, 2, 7, 8 (R911)
2	Flame Retardant Series.pdf	Pages 2–3	-50-/-51-	Sections 3, 8 (R912 specifications and drip-type description)
3	Flame Retardant Series.pdf	Page 4	-52-	Sections 3, 7, 8 (R912B)
4	Flame Retardant Series.pdf	Pages 5–6	-53-/-54-	Sections 3, 7, 8 (R915 specifications, processing, compliance)
5	Flame Retardant Series.pdf	Pages 7–8	-55-/-56-	Sections 4, 8 (R940 composition, processing, prohibitions)
6	Flame Retardant Series.pdf	Page 9	-57-	Sections 5, 7, 8 (R218)
7	Californium Curium – Functional Additives 1.09.pdf	Pages 3–4	Catalogue 55 / 83	Sections 1, 6, 8 (series catalogue, 63#, footnote)
8	Californium Curium – Functional Additives 1.09.pdf	Pages 53–61	-49-–-57-	Sections 2–5 (same text as the series volume)
9	Californium Curium – Functional Masterbatch 1.05-4.pdf	Page 3	Printed 10	Section 6 (masterbatch product introduction wording)
10	Californium Curium – Functional Masterbatch 1.05-4.pdf	Page 4	Friendly Reminder	Section 7 (drying and sample preparation notes)
11	Californium Curium – Functional Masterbatch 1.05-4.pdf	Page 5	-1-	Section 2 (M911 masterbatch)
12	Californium Curium – Functional Masterbatch 1.05-4.pdf	Page 13	-9-	Section 6 (M922 low-halogen wording)
13	Californium Curium – Functional Masterbatch 1.05-4.pdf	Page 14	-10-	Section 8 (M933)

Note: All parameters and descriptions in this document are sourced solely from the materials listed in the table above; items not listed in the source materials have been marked within the text as "Not listed in the source material". This document contains no pricing, customer names, certification numbers, or performance commitments. Terminology convention: "low-halogen" is the standard term; the halogen-free models (R911/R912/R912B/R915/R940/M911/M915/M918/M933) and the halogenated low-halogen model (M922) have been separately identified.