CB6954 Nylon 12/PA 12

Nylon 12/PA 12 Description

PA 12 is synthesised via ring‐opening polymerisation of laurolactam. It is a long‐chain polyamide with a moisture absorption level of 0.25–0.5%, compared with approximately 3% for PA 6, thereby ensuring dimensional stability in humid environments. Its molecular structure incorporates a reduced amide group density, which provides chemical resistance to fuels, oils, brake fluids (DOT3/DOT4), glycol‐based coolants and weak acids/alkalis, although the material remains susceptible to strong mineral acids and chlorinated solvents. With a density of 1.01–1.03 g/cm³, PA 12 facilitates lighter designs (reducing weight by 30–50% relative to rubber alternatives) and maintains flexibility at cryogenic temperatures down to –70°C, thereby reducing the risk of brittle fracture in low‐temperature applications. Unfilled grades typically show tensile strengths of 45–55 MPa, elongation of 200–300% and impact resistance; glass‐fibre reinforcement is frequently applied for structural components.

In industrial production, PA 12 is synthesised by either hydrolytic polymerisation (initiated by water at 270–300°C and 5–20 bar) or anionic polymerisation (a catalyst‐driven process for casting). The polymer is subsequently pelletised and undergoes solid‐state post‐condensation to increase the molecular weight. With a melting point of 178–180°C and an extensive processing window, PA 12 is suitable for extrusion, injection moulding and blow moulding. This facilitates the manufacture of multilayer fuel lines (PA 12/EVOH/PA 12).

Nylon 12/PA 12 Applications

Automotive (accounting for 60% of global demand): PA 12 is used in multilayer fuel lines (comprising an inner PA 12 layer with an EVOH barrier) to reduce hydrocarbon permeation; in brake hoses, which are reinforced with glass fibre and withstand hydraulic pressures in excess of 20 MPa; and in cooling tubes for electric vehicles subject to glycol fluids.

Additive Manufacturing: PA 12 is widely employed in SLS 3D printing (e.g., EOS PA 2200 powder) for producing functional prototypes, surgical guides and aerospace hinges. The powder exhibits consistent flowability and reliable sintering characteristics.

Industrial Fluid Systems: The material is utilised in the manufacture of hoses and pipes for oil and gas transfer, demonstrating a lifespan that is seven times longer than rubber alternatives. It is also employed in solar cable sheathing due to its resistance to ultraviolet light and weathering.

Emerging Uses: PA 12 is applied in hydrogen fuel lines designed for high-pressure conditions; in medical devices, including ISO 10993-compliant surgical instruments; and in flexible robotics where elastomer-modified grades are required.

Nylon 12/PA 12 Packaging

Products are packaged in customised cartons of various sizes according to the material dimensions. Smaller items are packed in PP boxes, while larger items are transported in custom wooden crates. Packaging procedures adhere to defined specifications and utilise appropriate cushioning materials to protect the products during transportation.

Packaging: Carton, Wooden Box, or Customised.

Please review the packaging details provided for reference.

Manufacturing Process

1.       Testing Method

(1)    Chemical Composition Analysis: The composition is determined using techniques such as GDMS or XRF to verify compliance with purity requirements.

(2)    Mechanical Properties Testing: Tensile strength, yield strength and elongation tests are conducted to assess material performance.

(3)    Dimensional Inspection: Measurements of thickness, width and length are taken to ensure adherence to specified tolerances.

(4)    Surface Quality Inspection: Visual and ultrasonic examinations are performed to identify defects such as scratches, cracks or inclusions.

(5)    Hardness Testing: Hardness is measured to confirm uniformity and mechanical reliability.

For detailed information, please refer to the testing procedures.

Nylon 12/PA 12 FAQs

Q1. What differentiates PA 12 from other nylons?

PA 12 exhibits moisture absorption in the range of 0.25–0.5%, which is significantly lower than that of PA 6 or PA 66. This low moisture uptake supports dimensional stability and consistent barrier performance in humid environments. The material also retains flexibility at cryogenic temperatures (down to –70°C) and demonstrates resistance to oils, fuels and chemicals.

Q2. What are the primary applications?

Primary applications include:

High-barrier food packaging for oily or frozen foods, coffee and cheese.

Medical sterilisation pouches that resist steam and EtO sterilisation.

Inflatable seals for aerospace and cleanroom environments.

Protective interlayers in composites and safety glass.

Corrosion-resistant coatings for metal pipelines.

Q3. What are the key performance properties?

The material exhibits low oxygen and carbon dioxide permeability. Its thermal operating range is from –70°C to +120°C, with short-term exposure up to 150°C. It demonstrates adequate puncture and abrasion resistance as well as elasticity. PA 12 complies with FDA and EC requirements for food and medical contact, and its optical translucency may be adjusted.

Related Information

1.       Common Preparation Methods

PA 12 is synthesised primarily by ring‐opening polymerisation (ROP) of laurolactam. Laurolactam is derived from butadiene via intermediates such as cyclododecatriene, cyclododecanone and cyclododecanone oxime, followed by a Beckmann rearrangement. The industrial process involves hydrolytic polymerisation, whereby laurolactam reacts with water at pressures of 5–20 bar and temperatures of 270–300°C to initiate ring opening, forming 12-aminododecanoic acid that then undergoes step‐growth polycondensation. In this process, amine groups attack lactam rings, releasing water and requiring 10–24 hours in vertical reactors (VK tubes) to achieve the desired molecular weight. Residual monomers are removed by vacuum stripping or hot‐water extraction. Alternatively, anionic polymerisation is used for casting applications; this method employs sodium hydride/N-acetyl caprolactam catalysts in molten laurolactam at 150–180°C, completing polymerisation in minutes without the application of pressure. Following polymerisation, the melt is extruded and pelletised, and it often undergoes solid‐state post‐condensation under vacuum to increase chain length before final processing into granules or powders.