Polycarbonate CAS 25037-45-0
Chelora Chemicals supplies optical, injection moulding and extrusion grades of polycarbonate to electronics, automotive, glazing and medical device producers worldwide. Every consignment leaves with a batch-specific COA covering melt flow rate, yellowness index, impact strength and moisture, the current SDS and full export documentation.
Also known as: PC · Bisphenol-A polycarbonate · Lexan type · Makrolon type · Polycarbonate resin
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Price, lead time and a sample COA for Polycarbonate, usually within one working day. We ship worldwide.
Request a Quote Email the DeskDocumentation
- Batch-specific COA (MFR, yellowness index, impact, moisture)
- Safety Data Sheet (SDS)
- Transport and export documents
- Third-party inspection on request
- Certificate of origin
What is Polycarbonate?
Polycarbonate is an amorphous engineering thermoplastic made from bisphenol-A, combining optical clarity with impact strength far beyond any other transparent polymer.
It is made either by interfacial polymerisation with phosgene or by the melt process with diphenyl carbonate, the latter avoiding phosgene entirely.
Applications span optical media and lenses, automotive glazing and lighting, electrical and electronic housings, medical devices and safety equipment.
PC is hygroscopic and hydrolyses in the melt, so drying is essential, and it is notch sensitive and attacked by several common solvents — both facts that part design must respect.
Why polycarbonate specifically
- Transparency with toughness. Light transmission near 90% combined with notched impact strength no other clear polymer matches.
- Dimensional stability. Amorphous structure gives low shrinkage and precise moulding, important for optical and electrical parts.
- Heat resistance. Glass transition around 145 °C allows service temperatures well above commodity polymers.
- Inherent flame performance. Achieves good UL ratings with modest flame retardant addition.
How Polycarbonate is Manufactured
Polycarbonate is made by interfacial or melt polymerisation of bisphenol-A, with the route affecting purity and colour.
- Bisphenol-A feed. Polycarbonate-grade BPA with very low colour is the critical raw material.
- Interfacial polymerisation. BPA in aqueous alkali reacts with phosgene at an organic-aqueous interface, giving high molecular weight polymer.
- Melt polymerisation. The alternative route transesterifies BPA with diphenyl carbonate under vacuum, avoiding phosgene and solvent.
- Washing and solvent recovery. Interfacial product is washed free of salt and catalyst, and solvent recovered.
- Devolatilisation. Residual solvent and monomer are stripped to very low levels.
- Compounding and pelletising. Stabilisers, UV absorbers, mould release and flame retardants are added to the grade recipe.
Typical Commercial Specification
Figures below are representative of a general-purpose injection moulding grade. Optical, extrusion and flame-retardant grades differ — tell us the application and we will send the matching sheet.
| Parameter | Typical Value |
|---|---|
| Appearance | Clear or tinted pellets, free of contamination |
| Melt flow rate (300 °C / 1.2 kg) | 3 – 80 g/10 min depending on grade |
| Density | 1.20 g/cm³ |
| Yellowness index | To grade, typically 2 max for optical |
| Light transmission | 88 – 90% for clear grades |
| Notched Izod impact at 23 °C | Typically 60 – 90 kJ/m² |
| Heat deflection temperature | Typically 125 – 140 °C at 1.8 MPa |
| Moisture as delivered | 0.02% max |
| Residual monomer and solvent | To grade, low ppm |
Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical formula | (C₁₆H₁₄O₃)ₙ |
| Appearance | Clear, water-white pellets |
| Density | 1.20 g/cm³ |
| Glass transition temperature | About 145 to 150 °C |
| Structure | Amorphous — no crystalline melting point |
| Moisture absorption | Hygroscopic, up to 0.35% at equilibrium |
| Drying requirement | To below 0.02% before processing |
| Chemical resistance | Poor to alkalis, ketones, esters and some hydrocarbons |
| Processing temperature | Typically 280 to 320 °C |
| Light transmission | 88 to 90% for clear grades |
| Incompatibilities | Alkalis, ammonia, amines, ketones, esters, chlorinated solvents |
Behaviour in the process
Polycarbonate is strong but has two well-known vulnerabilities that part design must address:
- Hydrolysis in the melt. Moisture above 0.02% causes chain scission at processing temperature, producing splay, brittleness and loss of impact.
- Notch sensitivity. Impact strength falls sharply at sharp corners and notches; generous radii are essential in part design.
- Environmental stress cracking. Attacked by alkalis, ketones, esters and some cleaning agents, especially under moulded-in stress.
- UV yellowing. Yellows outdoors without a UV stabiliser package or coextruded UV layer.
Polycarbonate Grades and Alternatives
Polycarbonate is bought by melt flow rate and grade family, with optical and flame-retardant requirements narrowing the choice.
| Material | Origin / type | When it is the right choice |
|---|---|---|
| Optical grade PC | High flow, very low yellowness | Lenses, optical media and lighting |
| Injection moulding grade | Medium flow | Housings, electrical parts and consumer products |
| Extrusion grade PC | Low flow, high molecular weight | Sheet, glazing and profile |
| Flame-retardant PC | FR package added | Electrical enclosures requiring UL ratings |
| PC/ABS blends | Alloy | Better flow and chemical resistance at lower heat resistance |
Stated plainly: PC/ABS alloys solve two PC weaknesses — flow and chemical resistance — at the cost of heat resistance and clarity. Where transparency is required, nothing substitutes for polycarbonate.
Industries We Supply Polycarbonate To
Polycarbonate serves electronics, automotive, construction, medical and safety markets.
Where Polycarbonate is Used
Electronics and automotive take the largest polycarbonate volumes, with sheet and glazing behind them.
Drying and processing
Polycarbonate must be dried to below 0.02% moisture, typically three to four hours at 120 °C in a desiccant dryer. Undried resin hydrolyses at 280 to 320 °C, producing splay marks, lower molecular weight and a dramatic loss of impact strength. As with PET, most PC processing complaints start at the dryer.
Design against stress cracking
Polycarbonate parts fail in service far more often from environmental stress cracking than from overload. Moulded-in stress from sharp corners, poor gating or excessive packing, combined with contact with cleaning agents, adhesives or alkaline media, is the usual mechanism. Annealing and generous radii both help.
Need a specific grade, purity and packing format?
Tell us the grade, the grade, melt flow rate and whether optical or flame-retardant properties are required, the packing format you can receive and the annual quantity. We will come back with a price, a lead time, a sample COA and the full documentation set.
Quality Control & Testing
Every lot is released against a batch-specific Certificate of Analysis with the grade's defining properties, including yellowness index for optical grades.
- Melt flow rate — at 300 °C and 1.2 kg, the primary processing indicator.
- Yellowness index and light transmission — the optical grade specifications.
- Notched Izod impact — confirming the toughness that defines the material.
- Heat deflection temperature — for parts with a thermal requirement.
- Moisture as delivered — confirming the resin was packed dry.
- Residual monomer and solvent — reported in ppm, relevant for medical and food contact grades.
Common Process Problems & Likely Causes
When polycarbonate causes trouble, it is usually drying, stress cracking or part design. This table is the shortcut our technical desk works through before anyone opens a complaint file.
| Symptom | Likely cause | What to check |
|---|---|---|
| Splay marks and brittle parts | Moisture causing hydrolysis in the melt | Dryer dew point, temperature and residence time |
| Parts cracking in service | Environmental stress cracking from chemical contact plus moulded-in stress | Chemical compatibility, gate design and annealing |
| Impact strength below specification | Molecular weight loss from overheating or wet resin | Moisture, melt temperature and MFR after moulding |
| Yellowing in the part | Overheating, long residence or UV exposure | Yellowness index, melt profile and UV package |
| Clarity poor or hazy | Contamination, moisture or regrind content | Pellet appearance, drying and regrind ratio |
| Short shots on thin sections | Melt flow rate too low for the part | MFR against wall thickness and flow length |
Packaging, Storage & Shipping
- Standard packing. 25 kg foil-lined bags, 500 to 1000 kg jumbo bags and octabins, all moisture barrier packed.
- Moisture protection. PC is hygroscopic; keep packaging sealed until use and dry immediately before processing.
- Drying. Three to four hours at 120 °C in a desiccant dryer with a dew point of −30 °C or lower.
- Storage. Dry, covered warehousing at ambient temperature on pallets.
- Chemical exposure. Keep away from ammonia, amines, alkalis, ketones and esters, which attack the polymer even in vapour form.
- Regrind control. Limit regrind content and heat history; repeated processing degrades molecular weight.
- Shelf life. Typically 24 months in sealed moisture barrier packaging.
- Transport classification. Not classified as dangerous goods for transport.
Hazards & Safe Handling
Polycarbonate is an inert polymer with no significant health hazard in normal handling. The practical concerns are molten polymer burns, hot dryers and fume from overheating.
- Inert in normal handling. Not classified as hazardous. Pellets present no chemical risk in storage or transport.
- Molten polymer burns. Melt at 280 to 320 °C adheres to skin and causes severe burns; use proper PPE at the machine.
- Hot dryer surfaces. Dryers run at 120 °C; burns from hoppers and ducting are a real risk.
- Thermal decomposition. Overheating releases phenolic and carbonate decomposition products; ventilate processing areas.
- Slip hazard. Spilled pellets are a serious slip hazard; clean up promptly.
- BPA considerations. Residual BPA is controlled at very low levels; food contact and medical grades carry specific documentation.
Regulatory & Compliance Notes
Polycarbonate is unregulated for transport, with BPA-related restrictions affecting some consumer applications. The notes below are orientation rather than legal advice.
- GHS classification. Not classified as hazardous.
- Transport. Not classified as dangerous goods. Standard packaged cargo documentation applies.
- Food contact. Food grades must comply with EU 10/2011 and FDA regulations, with BPA migration limits that have tightened significantly.
- Consumer restrictions. Polycarbonate infant feeding bottles are banned in the EU and several other jurisdictions because of BPA.
- Medical devices. Medical grades require biocompatibility documentation under ISO 10993 and formulation change notification.
- Flame ratings. Electrical applications typically require UL 94 classification, with the FR grade and thickness both specified.
We Supply Polycarbonate Worldwide
Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Polycarbonate from India and from partner sources to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation, transport paperwork and freight so the material arrives ready to use.
- Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
- Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other ports arranged where routing and cargo rules allow.
- Documentation. Commercial invoice, packing list, certificate of origin, COA, SDS and the transport declaration issued as a complete set.
- Flexible volumes. From a pallet of bagged resin up to repeat bulk shipments on a supply contract.
- Supply continuity. Because we are independent of any one producer, a plant turnaround or a shipping disruption at one source does not have to become your stock-out.
Buying Polycarbonate from Chelora
We are an independent sourcing and supply partner. For polycarbonate that means settling three things at enquiry: the grade and melt flow rate your part requires, whether optical clarity or flame retardancy is needed, and whether medical or food contact documentation applies.
- Documentation on every lot. Batch-specific COA (MFR, yellowness index, impact, moisture), plus SDS and the full transport paperwork.
- Analysis before commitment. Representative analysis shared ahead of a commercial order so your lab can qualify the material.
- Quantities. From a pallet of bagged resin through to full bulk shipments on contract supply.
- Grade matching. Optical, injection, extrusion or flame-retardant grade at the melt flow rate and yellowness index your application requires.
- Inspection. Independent third-party inspection available at loading when the contract requires it.
- Related products. Bisphenol-A, Acrylonitrile Butadiene Styrene Resin, Phenol and other feedstocks alongside Polycarbonate from one supplier.
How ordering works
- Send the enquiry. Product, grade or purity, quantity, destination port and the Incoterm you buy on. If you have a spec sheet, attach it — it saves a round trip.
- We quote. Price, lead time, packing format and a sample COA, normally within one working day.
- Qualify the supply. For first orders or critical applications, we share the analysis and handling documentation so your technical and safety teams can sign off before you commit.
- Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
- Allocation and QC. Material allocated and released against a batch-specific COA, with an independent inspection where the contract calls for it.
- Ship and document. Filled, labelled and loaded with the full export document set, and tracked through to arrival.
Polycarbonate — Common Questions
The questions our technical desk is asked most often about Polycarbonate. If yours isn't here, call or email and you will reach someone who knows the chemistry.
What is the CAS number of polycarbonate?
The CAS number for bisphenol-A polycarbonate is 25037-45-0, and it is classified under HS code 3907.40. As a polymer it is exempt from REACH registration, though BPA is not.
What is polycarbonate used for?
For electrical and electronic housings, automotive lighting and glazing, construction glazing sheet, optical lenses and media, medical devices, and safety equipment such as visors and machine guards.
Do you supply polycarbonate worldwide?
Yes. Chelora Chemicals supplies and exports polycarbonate worldwide — across Asia Pacific, Europe, the Middle East, Africa and the Americas, as well as throughout India, in moisture barrier bags, jumbo bags and octabins.
Why must polycarbonate be dried before processing?
Because it is hygroscopic and hydrolyses at processing temperature. Moisture above 0.02% causes chain scission, producing splay marks, lower molecular weight and a sharp loss of impact strength.
How is polycarbonate manufactured?
Either by interfacial polymerisation of bisphenol-A with phosgene in a two-phase system, or by melt transesterification of BPA with diphenyl carbonate under vacuum, which avoids phosgene entirely.
Why do polycarbonate parts crack in service?
Usually environmental stress cracking: contact with alkalis, ketones, esters or cleaning agents combined with moulded-in stress from sharp corners or excessive packing. Generous radii, careful gating and annealing all reduce it.
What chemicals attack polycarbonate?
Alkalis, ammonia and amines, ketones, esters, and some chlorinated solvents. Even vapour exposure can craze parts, so storage and assembly environments matter as much as direct contact.
Is polycarbonate hazardous?
No. It is an inert polymer not classified as dangerous goods. The practical hazards are burns from molten polymer and hot dryers, and fume if the material is overheated.
Is polycarbonate food contact approved?
Specific grades are, under EU 10/2011 and FDA regulations, but BPA migration limits have tightened and polycarbonate infant feeding bottles are banned in the EU and several other jurisdictions.
What are the drying conditions for polycarbonate?
Typically three to four hours at 120 °C in a desiccant dryer with a dew point of −30 °C or lower, with dried resin fed directly to the machine.
What is PC/ABS and when should I use it?
An alloy of polycarbonate and ABS that improves flow and chemical resistance at the cost of heat resistance and transparency. It is widely used for automotive interiors and electronic housings where PC alone is difficult to mould.
What packing sizes are available?
25 kg foil-lined bags, 500 to 1000 kg jumbo bags and octabins, all moisture barrier packed. Orders run from a pallet of bagged resin up to full container loads.
Ready to source Polycarbonate?
Send us your specification, grade and annual volume. You will get a price, a realistic lead time and a sample COA from someone who understands what the material has to do in your process — delivered anywhere in the world.