LATI Latiohm 83-07 PD11 CNT PA12, Impact Modified is a carbon nanotube–filled polyamide 12 compound in which an impact-modifier package is dispersed together with the conductive filler during twin-screw compounding. The grade is positioned between unreinforced PA12 and carbon-black-filled conductive PA12: the CNT network provides electrostatic dissipation without the high filler loadings typical of carbon black, while the impact modification restores part of the ductility that conductive fillers otherwise remove. The designation identifies a polyamide 12 base, the impact-modified variant, and the carbon nanotube filler type; LATI technical documentation remains the authoritative source for the exact suffix logic. Typical applications include injection-moulded housings, clips, and trays requiring surface resistance below 10⁹ Ω/sq in ESD-protected areas under IEC 61340-5-1 and where PA12’s low moisture uptake relative to PA6 or PA66 preserves electrical stability across humidity cycles. The base PA12 absorbs approximately 0.2 % moisture at 23 °C and 50 % RH under ISO 62, whereas unmodified PA6 can absorb 2.5–3.0 % in the same environment, which supports the low-humidity electrical stability claim.

In electrostatic dissipation applications, the product is selected where a permanent, non-migrating conductive pathway is required. Unlike topical antistatic coatings or low-molecular-weight migratory additives, the carbon nanotube network is part of the polymer bulk. The surface resistivity of CNT PA12 grades is less dependent on adsorbed moisture than that of carbon black compounds because conduction is primarily electronic through filler–filler contacts, not ionic through a water layer. However, the actual value in a moulded part depends on flow orientation, weld-line position, and local shear history. Surface resistance measurements should therefore be made on production-representative parts, not only on edge-gated plaques. The relevant test geometry and electrode configuration follow IEC 62631-3-2; for ESD control programmes, the limits in IEC 61340-5-1 classify protected areas and packaging.

Which processing parameters most affect the CNT network and impact performance?

Pre-drying in a desiccant-bed dryer is required. Moisture in PA12 above 0.10 wt% to 0.15 wt% at the hopper can depress melt viscosity and create surface splay. A drying schedule of 70–80 °C for 4–8 h with a dew point at or below −30 °C is typical for PA12. Longer residence at high temperature can yellow the material and reduce impact values; drying time should be interrupted when the target residual moisture measured by ISO 15512 is achieved.

Melt temperatures for impact-modified PA12 fall between 220 °C and 250 °C, with the nozzle held in the upper half of that range. Mould temperatures between 40 °C and 80 °C allow sufficient crystallisation and dimensional control. High-shear screw elements can damage the CNT network and shorten the notched impact response; a moulding machine using excessive back pressure or screw speed should be evaluated for melt-temperature rise beyond the upper limit. In-line melt temperature and pressure sensors are recommended to keep the specific energy input stable across batches. Injection speed should be moderate because excessive shear can align nanotubes near the wall and reduce surface conductivity.

Carbon-black-filled PA12 compounds usually require filler loadings of 10–20 wt% to enter the conductive range, and the resulting compounds often show reduced elongation at break and notched impact strength. The CNT route can lower filler content because of the high aspect ratio of the nanotubes. This creates a different property profile: the impact-modified base retains more of the original PA12 toughness, and the surface is less likely to slough conductive particles onto adjacent components in cleanroom or optical assembly environments. Quantitative comparison against a specific carbon-black grade must be made using ISO 527-2 tensile bars and ISO 179-1/1eA notched Charpy specimens prepared from the same mould geometry. Published comparative data for this exact LATI grade is limited; the available technical datasheet should not be extrapolated beyond the stated specimen thickness and conditioning state.

Compared with non-impact-modified conductive PA12, the impact-modified grade is selected when the component must survive snap-fit assembly or cold-impact events. The trade-off is often a slight reduction in tensile modulus and surface hardness relative to an unmodified conductive PA12, but the notched impact strength is higher. The exact balance is visible in the stress–strain curve: impact modification usually increases elongation at yield or break while lowering the modulus. Designers should compare the secant modulus from ISO 527-2 at 1 % strain rather than only the initial tangent because the impact modifier affects low-strain stiffness more than ultimate strength.

When the part faces combined fuel exposure and low-temperature impact

Polyamide 12 is preferred over PA6 and PA66 in automotive fuel vapour and pneumatic systems because of its lower equilibrium moisture uptake, better dimensional stability, and resistance to zinc chloride stress cracking. The impact-modified conductive version extends this chemistry to clips, brackets, and sensor housings that must dissipate static charge while retaining toughness after cold conditioning. In such applications, validation includes notched Charpy tests at −30 °C or −40 °C according to ISO 179-1/1eA, plus retained surface resistivity after fuel immersion under a defined test fluid, often ISO 1817 or an OEM-specific fuel. Users must confirm that fuel resistance of the impact modifier package is acceptable because some impact modifiers can compromise long-term hydrolysis or fuel ageing performance. Published data for this specific configuration is limited in public sources; application approval therefore depends on component-level testing under the end-use temperature and chemical environment.

Processors moving from an unreinforced PA12 grade should expect a higher melt viscosity and a more pronounced shear-thinning response from the CNT network. Gate locations, runner dimensions, and venting should be assessed using short-shot studies and pressure-drop measurements on the intended production press. A clamp force of at least 0.6–0.8 kN/cm² of projected area is common for semi-crystalline polyamides, but the actual requirement depends on wall thickness and flow length. The use of hot runners is possible; however, dead spots, long residence time, and narrow gates can create local CNT orientation and resistance variation. Two-shot or overmoulding operations should verify adhesion to the substrate and the influence of the substrate’s thermal mass on cooling rate and crystallinity.

The technical tension in this product class lies in the competing requirements of conductive filler percolation and impact-modifier phase separation. Carbon nanotubes form a conductive network when dispersed at or above the percolation threshold; however, finely dispersed impact-modifier domains can interrupt the network unless the compounding process creates a co-continuous or selectively localised filler distribution. In practice, this means that the same nominal formulation can show different surface resistivity depending on the screw configuration, melt temperature, and injection speed. Batch-to-batch conductivity consistency should therefore be monitored with production-representative plaques, and the incoming material should be certified for both mechanical and electrical performance. Regrind use must be approached with caution. Repeated mechanical recycling of CNT-filled PA12 lowers the aspect ratio of the filler if high-shear regrind size-reduction equipment is used, and the conductivity may shift after multiple heat histories. Validated regrind ratios of 20–30 wt% are commonly allowed for unfilled PA12, but for conductive compounds the specific limit must be established through surface resistance testing per IEC 62631-3-2 on moulded parts from a blend of virgin and regrind. Published data for this specific configuration is limited; therefore, no universal regrind percentage is claimed here.

Table 1 lists the principal test standards used to characterise the grade during incoming inspection and first-article qualification. The table is a compliance checklist, not a substitute for the LATI datasheet; acceptance windows must be taken from the current product specification.

Within the LATI Latiohm range, carbon nanotube grades are offered in several base resins. The PA12-based 83-07 PD11 CNT grade is selected over PA6 or PA66 conductive grades when lower moisture absorption, better low-temperature impact, and chemical resistance to hydrocarbons are required. It is selected over a glass-fibre-reinforced conductive PA6 when dimensional stability in humid environments matters more than short-term tensile modulus. However, the PA12 base cannot match the heat deflection temperature of glass-filled PA66 conductive materials; therefore, applications above approximately 100 °C under load should be reevaluated with the heat deflection temperature obtained under ISO 75-2. When migration from a carbon-black conductive PA12 grade is planned, the most important differences are not only electrical but also rheological: gate freeze, pressure drop, and orientation at weld lines can shift the effective surface resistance in the finished component. Weld-line conductivity should always be validated on a tooled prototype using the exact production gate configuration, not inferred from a simple plaque.

The CNT content requires a safety review in the processing environment. Although CNTs are bound in a polymer matrix during compounding, subsequent machining, sanding, or regrinding can generate dust. Exposure controls should follow national occupational exposure limits for carbon nanotubes and organic polymer dust; ventilation and HEPA filtration are standard engineering controls. The base PA12 and impact modifier may comply with REACH and RoHS requirements, but the finished part must be assessed for the specific application. No food-contact claim is made unless the exact grade is listed under the relevant food-contact regulation. In operations where surface resistivity is a safety-critical parameter, the moulding area should maintain a controlled humidity and record electrical measurements from each lot before release to production.