Bada BADAMID PA12 GF30 H natural LB is a heat-stabilized polyamide 12 injection molding compound reinforced with 30% by weight glass fiber and delivered in a dry state. Under ISO 1043-1, the standardized base description is PA12-GF30; the supplier suffix H identifies heat stabilization, natural indicates the absence of carbon black or colored masterbatch, and LB is a Bada-internal grade modifier that must be decoded using the lot-specific raw material specification. The long aliphatic segment between amide groups in PA12 lowers amide-group density compared with PA6 and PA66, which reduces equilibrium moisture uptake and changes chemical resistance, dimensional stability, and low-temperature behavior. The 30% glass fiber level raises tensile modulus and heat distortion temperature relative to unfilled PA12, but it also increases melt viscosity, produces fiber-orientation shrinkage, and reduces weld-line strength. The compound is specified for injection-molded parts requiring high stiffness, creep resistance, and resistance to oils, greases, and road-salt stress cracking, such as sensor housings, pump bodies, pneumatic valve housings, clips, and brackets. Published application performance data for this specific Bada configuration is limited; part-level validation with the final gate location and service fluid is required.

Because the grade is supplied dry, residual moisture is typically below 0.10% by weight as measured by ISO 15512. Sealed packaging preserves that condition. Once opened in a production environment above 60% relative humidity, surface adsorption and bulk absorption begin within hours. Melt processing of moisture-laden PA12 GF30 hydrolyzes the polyamide matrix, reduces molecular weight, and produces gas splay on visible surfaces. Pre-drying at 80 °C to 90 °C in a dehumidifying dryer with a dew point below -30 °C for 4 h to 8 h is the standard correction. Target residual moisture is below 0.10% by weight. Vacuum drying at 80 °C for 6 h is an alternative for small batches. Regrind that has been stored in open containers should be dried under the same conditions, and glass dust should be removed to prevent hopper bridging and inconsistent shot weights.

What Limits the Molding Window When Glass Fiber Is Dispersed in PA12?

The processing window is narrower than for unfilled PA12 because the glass fiber raises viscosity and the polyamide matrix has limited residence-time tolerance. Typical starting melt temperatures are 240 °C to 270 °C, with mold temperatures from 60 °C to 100 °C. Higher mold temperature improves fiber wet-out and reduces exposed surface glass but increases cycle time and post-crystallization shrinkage. Clamp force should be estimated from projected area; a first-pass range of 0.5 kN/cm² to 0.8 kN/cm² is used for glass-filled semi-crystalline polyamides, but cavity-pressure sensors are preferred. Switchover from injection to holding pressure at 95% to 98% of full part volume avoids gate overpacking, fiber breakage, and delamination at weld lines.

The compound is produced on a co-rotating twin-screw extruder with L/D ratio typically between 40:1 and 52:1. Glass fiber is fed downstream after the PA12 base resin is fully molten. Downstream feeding retains longer fibers and reduces screw wear. If glass fiber is introduced at the main feed, the initial mixing zones grind the fiber, torque increases, and tensile modulus may fall below the expected dry-molded range. At the injection molding machine, a general-purpose nylon screw with compression ratio 1.8 to 2.2 and L/D 20:1 to 25:1 is acceptable, but hardened nitrided steel or bimetallic barrel linings, hard-faced check rings, and wear-resistant nozzle tips are required for production campaigns above 20,000 cycles. Back pressure should be held between 0.3 MPa and 1.0 MPa to maintain melt homogeneity without excessive fiber attrition. Residence time at melt temperature should remain below 10 min for natural heat-stabilized grades; longer exposure causes yellowing, surface gloss variation, and notched-impact loss. Hot runner systems should use open-flow nozzles, heated manifolds with minimum dead spots, and no reverse-taper channels because glass fibers accumulate in stagnation zones. Valve-gate systems are acceptable when the valve pin and gate insert are wear-resistant. At mold temperatures below 60 °C, parts may freeze with low crystallinity and show progressive dimensional change in service; at mold temperatures above 100 °C, ejector forces increase and cycle time becomes unfavorable.

Mechanical Property Profile Under Dry-Molded Conditions

Dry-molded values differ from conditioned values. The dry state means specimens are tested as molded with residual moisture below 0.10% by weight. After equilibrium at 23 °C and 50% relative humidity, tensile modulus and strength decrease while impact toughness increases in unfilled polyamides; glass reinforcement reduces the magnitude of that shift. The following table gives representative dry-molded ranges for commercial heat-stabilized PA12-GF30. The ranges are not a batch certificate and must not replace supplier-specific datasheets or ISO 527 and ISO 179 test data for final part design.

The 30% glass fiber content produces orientation-dependent mechanical behavior. In flow direction, tensile modulus and strength are higher; transverse to flow, elongation at break and notched impact are lower. Differential shrinkage is typical: flow-direction shrinkage is 50% to 70% lower than transverse shrinkage. Flat parts with uneven wall thickness can warp when gate position creates unbalanced flow. Mold-filling simulation with fiber-orientation tensors is recommended when flatness tolerance is below 0.2% of the relevant dimension. Weld lines in glass-reinforced polyamide retain 30% to 50% of the strength of a comparable unreinforced weld line; gates should be positioned to move weld lines away from tensile stress concentrations. Thin-wall sections below 1.0 mm combined with 30% glass fiber may freeze before complete filling; direct sprue gating into thin sections creates high shear heating and strong fiber alignment at the gate, which can produce surface streaks and weak gate regions.

Quality documentation for a PA12-GF30 compound should include density by ISO 1183-1, glass fiber content by ashing according to ISO 3451-4, moisture by ISO 15512, and melt viscosity under the supplier’s specified conditions. For a nominal 30% compound, an ashing result of 28% to 32% is a common acceptance window, but the supplier’s certificate of analysis defines the final interval. The base PA12 polymer may be assessed under EU Regulation No 10/2011 for food-contact applications only when article-specific migration testing is available; glass fiber and heat stabilizers are not automatically covered by a resin-only compliance statement. For industrial components, REACH Regulation (EC) No 1907/2006 and the RoHS Directive 2011/65/EU apply as horizontal chemical regulations; compliance is documented at lot level by the raw material supplier. Operating limits include direct outdoor exposure: natural PA12 without carbon black or UV stabilization will chalk and embrittle under prolonged ultraviolet radiation. Contact with strong acids, particularly formic acid and hydrochloric acid, causes hydrolysis and stress cracking. Condensation on cold pellets moved into warm humid air must be avoided because surface moisture can create processing defects even when bulk moisture remains low.

When PA12 GF30 Replaces PA6 GF30 or PA66 GF30 in Fluid-Contact Components

The replacement logic compares short-term dry strength with long-term dimensional and chemical stability. PA66 GF30 dry typically shows tensile strength in the 170–190 MPa range; PA12 GF30 lies at 110–130 MPa. PA12 absorbs less moisture at equilibrium. At 23 °C and 50% relative humidity, unfilled PA6 reaches approximately 2.8–3.0% water content, PA66 reaches 2.5–2.8%, and PA12 reaches 1.5–1.7%; with 30% glass fiber, the effective weight percentages are diluted by the non-hygroscopic filler. Lower moisture uptake means less dimensional growth and less loss of tensile modulus in humid service. The density advantage also matters: PA12 GF30 at 1.22–1.24 g/cm³ is approximately 10% lower in mass at equal volume than PA66 GF30 at 1.35–1.38 g/cm³.

PA12 also has a lower melting point than PA66: approximately 175–180 °C versus 260 °C. That lowers processing energy and allows lower barrel temperatures, but it also limits short-term thermal resistance. Although glass fiber raises HDT/A to 155–170 °C, PA66 GF30 dry may have HDT/A above 230 °C; therefore PA12 GF30 is not a direct replacement where exposure above 170 °C predominates. For components exposed to road de-icing salts, PA12 grades are selected because the longer aliphatic chain reduces susceptibility to salt-induced environmental stress cracking compared with PA6 and PA66. Comparative stress-cracking resistance is evaluated with ISO 22088-2 or ISO 22088-4. In fuel-contact and air-brake systems, PA12 has a history of use where low fuel permeation and resistance to zinc chloride are required; published data for this specific Bada configuration is limited, and validation on the final part with the actual service fluid is mandatory.

Reinforcement Type Alters Stiffness, Shrinkage, and Surface Appearance

Relative to unfilled PA12, the GF30 H natural LB grade replaces ductile matrix deformation with fiber-dominated stiffness. Dry unfilled PA12 typically shows tensile modulus near 1,400–1,600 MPa; the 30% glass fiber grade reaches 6,500–7,500 MPa. Elongation at break falls from 20–50% or higher to 3–5%, and notched impact is reduced. Heat distortion temperature under 1.8 MPa load increases by roughly 100 K or more. These changes make the GF30 grade suitable for structural brackets, housings, and pump components where creep and dimensional stability under load outweigh high elongation at failure.

Compared with mineral-filled PA12, glass fiber gives higher tensile strength and better impact retention at the same filler weight fraction, but it produces more visible surface fiber, higher anisotropy, and more mold wear. Compared with carbon-fiber reinforced PA12, the glass-fiber grade has lower modulus and no significant electrical conductivity; it is therefore used where galvanic insulation or radar transparency is required. The heat-stabilized H designation indicates resistance to oxidative degradation at elevated service temperature; continuous-use temperature ratings should be established by the end user using thermal aging data from the supplier, part wall thickness, load, and standards such as IEC 60216 or UL 746B.