INEOS Styrolution Luran SAN 348Q is a styrene-acrylonitrile copolymer pellet grade intended for injection moulding of transparent and opaque components. The designation denotes a medium-flow material with a melt volume-flow rate of 22 cm³/10 min at 220 °C under a 10 kg load when measured in accordance with ISO 1133-1:2022. The dried polymer has a density of 1.08 g/cm³ by ISO 1183-1, a tensile modulus of 3700 MPa and a tensile stress at break of 67 MPa when tested as a 1A specimen under ISO 527-2/1A/1, and a notched Charpy impact strength of 2 kJ/m² at 23 °C by ISO 179-1/1eA. The Vicat softening temperature B/50 is 96 °C under ISO 306. Water absorption at saturation in water at 23 °C is 0.2 % by ISO 62. Moulding shrinkage on edge-gated plaques ranges from 0.3 % to 0.7 % by ISO 294-4. The resin is supplied as unpigmented pellets, and the injection moulding melt temperature window is 220 °C to 260 °C; mould temperature is 40 °C to 80 °C. Pre-drying at 80 °C for 4 h in a dehumidifying dryer is required when moisture measured by ISO 15512 exceeds 0.1 %. Principal applications include cosmetic caps, fragrance pump housings, transparent lids, and small appliance covers requiring a stiff, chemically resistant styrenic matrix.

What Differentiates Luran SAN 348Q from Other Styrenic Copolymers?

The acrylonitrile comonomer in Luran SAN 348Q differentiates the material from general-purpose polystyrene and high-impact polystyrene in solvent resistance and surface hardness. The polymer contains no polybutadiene rubber phase; it is therefore not an ABS and does not show the stress whitening typical of rubber-toughened styrenics. Under ISO 527-2/1A/1, the tensile modulus of 3700 MPa is higher than that of medium-impact ABS but lower than that of glass-fibre-reinforced styrenics. The notched Charpy impact strength of 2 kJ/m² at 23 °C is lower than ABS, which typically falls above 10 kJ/m² in the same test; this imposes a design constraint for snap-fits under impact. Across commercial styrene-acrylonitrile grades, melt volume-flow rates range from below 10 cm³/10 min to above 45 cm³/10 min under ISO 1133-1:2022; Luran SAN 348Q occupies the medium-flow segment. Higher-flow grades may offer shorter filling times but generally show lower Vicat temperature and notched impact. Lower-flow grades provide higher impact and heat resistance, but require higher melt temperatures or thicker wall sections.

The Q designation is associated with low residual monomer and reduced odour/taste contribution relative to general industrial SAN grades; published data for this specific configuration is limited, and the current regulatory datasheet must be checked before using the grade in food-contact or cosmetic packaging. Compared with polymethyl methacrylate, Luran SAN 348Q has lower light transmission and UV stability but higher chemical resistance to certain cosmetic solvents and lower density. Compared with polycarbonate, the material has lower impact strength and continuous-use temperature but lower melt viscosity; polycarbonate grades with similar heat resistance typically require processing above 280 °C. The material is not classified as a high-clarity optical polymer; optical applications requiring haze below 1 % under ASTM D1003 may require a dedicated optical SAN or PMMA. The specific light transmission of Luran SAN 348Q should be confirmed on a 2 mm plaque and is influenced by mould surface polish and thermal history.

When Thin-Wall Injection Moulding Dictates Melt Temperature and Clamp Force

Thin-wall moulding of Luran SAN 348Q in cavities with wall sections from 0.8 mm to 1.2 mm requires the melt temperature to be set in the upper portion of the processing window, 240 °C to 260 °C, because melt viscosity rises sharply below 220 °C. The material flows best through short gates with land lengths below 1 mm and gate diameters from 0.8 mm to 1.5 mm. On a 1000 kN hydraulic injection moulding machine with a 25 mm general-purpose screw of 20:1 L/D, starting parameters are back pressure of 5 MPa to 10 MPa, screw surface speed of 100 mm/s to 200 mm/s, and metering stroke set so that cushion remains 3 mm to 6 mm. The injection profile is normally controlled by cavity pressure rather than velocity; cavity pressure at the gate is maintained at 40 MPa to 60 MPa during packing. Clamp force is calculated from the projected part area and the estimated cavity pressure; for transparent lids with projected areas of 100 cm² to 400 cm², machines from 800 kN to 1500 kN are generally adequate. Venting depths of 0.02 mm to 0.04 mm on the parting line prevent burn marks and knit-line defects. Hot-runner manifolds must be fully purged and free of PVC or polycarbonate residues, because these resins degrade at SAN processing temperatures and produce black speck contamination. Residence time at 260 °C should not exceed 6 min; longer residence increases MVR and yellowness, and lowers notched Charpy impact. The gate freeze time is estimated from part thickness and mould temperature; early gate freeze produces sink marks and excessive packing pressure. Published data for this specific configuration is limited; mould-flow simulation using the measured viscosity curve is required for production tools.

Chemical resistance of Luran SAN 348Q is governed by the styrene-acrylonitrile matrix and is evaluated by immersion under ISO 175. At 23 °C, the material is resistant to dilute acids, dilute alkalis, and many aliphatic hydrocarbon oils; it is not resistant to aromatic hydrocarbons, chlorinated solvents, concentrated esters, or ketones. Cosmetic emulsions containing ethanol above 50 % by volume can initiate environmental stress cracking in areas with high moulded-in residual stress, particularly around sharp threads and snap-fits. Published data for this specific configuration is limited; compatibility tests with the actual formulation and at the worst-case temperature are required. If alcohol-based fragrance formulations are used in closures, stress concentrations should be minimized by generous radii and by optimizing packing pressure. Mould release agents should not be applied to visible surfaces because they reduce adhesion and may cause local haze under ASTM D1729 visual inspection. Additives that exude, including some flame retardants and plasticizers, are incompatible because they lower hardness and may promote solvent attack. Colour masterbatches should use a SAN carrier resin; polyolefin carriers form visible delamination and should not be used.

For reused material, transparent parts should contain no more than 20 % by weight of clean regrind; higher regrind additions may increase yellowness index measured by ISO 11664-4 and reduce Charpy impact. The regrind must remain below 0.1 % moisture by ISO 15512 to prevent splay. Without UV stabilizer, SAN exposed to weathering under ISO 4892-2 develops yellowing and embrittlement; outdoor applications require a UV-stabilized grade or opaque coating. The product is not suitable for continuous use above the Vicat softening temperature B/50 of 96 °C under load, and prolonged contact with strong mineral acids or oxidizing chemicals is not recommended. Dimensional stability is affected by water absorption of 0.2 % by ISO 62; this is low relative to polyamide but should be considered in precision parts.

Compliance Verification for Food-Contact and Cosmetic Packaging

Regulatory status for Luran SAN 348Q is application-specific. The resin is subject to Regulation (EC) No 1907/2006 as amended and may be subject to Annex XVII restrictions. For electrical or electronic applications, RoHS Directive 2011/65/EU Annex II applies to the finished component. For food-contact articles in the European Union, Framework Regulation (EC) No 1935/2004 and Regulation (EU) No 10/2011 control the finished item; acrylonitrile monomer specific migration limit and total migration limits are given in Annex II and Annex V respectively. Migration kinetics are concentration-dependent and temperature-dependent; the diffusion coefficient increases with temperature, so hot-fill or microwave conditions require separate verification. Compliance cannot be assumed from resin grade alone, because migration depends on wall thickness, contact time, temperature, and simulant. For the United States, 21 CFR 181.32 may be referenced for styrene-acrylonitrile copolymers when conditions of use are satisfied; this does not exempt the finished article from overall migration and organoleptic testing. For cosmetics packaging, Regulation (EC) No 1223/2009 applies to the finished cosmetic product, and packaging must not transfer constituents that alter safety or stability. Published data for this specific configuration is limited. The current INEOS Styrolution product safety datasheet and regulatory certificate must be consulted before a packaging qualification is drafted.

Extrusion Compounding Limitations and Regrind Recycling Boundaries

If Luran SAN 348Q is compounded on a twin-screw extruder, the recommended machine configuration uses 36:1 to 44:1 L/D with atmospheric and vacuum venting. The barrel profile is set from 220 °C in the feed throat to 240 °C at the die, with melt temperature not exceeding 260 °C. Vacuum devolatilization at absolute pressure below 20 kPa removes residual moisture and unreacted acrylonitrile. For a 25 mm to 40 mm co-rotating twin-screw extruder, screw speeds from 300 rpm to 600 rpm are typical for dispersion of liquid colorants; torque must be monitored against gearbox limits because the melt remains viscous at low temperatures. Strand pelletizing is preferred to underwater pelletizing because rapid cooling can induce surface voids if moisture becomes trapped. The material should not be compounded with polycarbonate, PVC, or polyamide; these resins are incompatible with SAN and form delamination or degradation products at SAN processing temperatures. The purge sequence after shutdown should use white ABS or general-purpose polystyrene; leaving SAN in a hot sprue bushing or hot-runner manifold without purging can result in carbonized deposits on the next production start-up.

Regrind use in transparent parts is limited by optical degradation rather than mechanical flow. Clean regrind from sprues and runners may be added at 20 % by weight when the final part is inspected under ASTM D1729. Above 20 %, yellowness index measured under ISO 11664-4 may increase, and the notched Charpy impact strength under ISO 179-1/1eA may fall below the virgin value. The regrind must be free of dust, grease, and incompatible polymers. If automatic recycling is used, granulator screen size of 6 mm to 8 mm and a homogenizing hopper are recommended to prevent feed blockages. The material is not intended for outdoor use without stabilization; if regrind lot is stored outdoors, moisture uptake above 0.1 % is possible even in sealed bags when relative humidity exceeds 60 %. In such cases, drying at 80 °C for 4 h must be repeated.