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PROCESSING GUIDETHERMA-TECH THERMALLY CONDUCTIVEFORMULATIONS
Therma-Tech Therma-Tech Thermally Conductive Formulations have been engineered to combine the heat transferand cooling capabilities of metals with the design freedom, weight reduction and cost advantages ofthermoplastics. These materials provide the benefits of proprietary conductive additive technologies andthe performance of select engineering thermoplastic resins. Therma-Tech formulations have been shownto improve thermal conductivity by 50-100 times that of conventional plastics and can be used in a widerange of thermal management applications.Injection Molding ParametersBase ResinPPAPPSPA 6/6PA 12Rear 490(227–254)440–480(227–250)Center 510(243–266)460–510(238–266)Front 302 –530(260–277)Melt Temperature F ( 0(271–300)500–530(260–277)Mold Temperature F ( 0(66–93)150–200(66–93)Barrel Temperatures F ( C)*Pack and Hold Pressure50–80% of Injection PressureInjection Velocity1.0–3.0 in/secBack Pressure25–100 psiScrew Speed25–75 rpmDrying Parameters F ( C)6 hours @ 175 (80)CushionScrew Compression RatioNozzle TypeClamp Pressure6 hours @ 300 (150)3 hours @ 180 (82)0.125–0.250 .5:1General PurposeGeneral PurposeReverse TaperReverse Taper4–5 tons/in2 of projected area of cavities and runner system* Barrel temperatures should be elevated for compounds designed for electrical insulative properties.2Therma-Tech3 hours @ 180 (82)
Start Up & Shut DownPurge CompoundRecyclingRecommendationsHDPE or HIPSRecycling Therma-Tech up to 20% is permissible. Testing the application ishighly recommended to determine the effect recycling has on the desiredphysical properties.Mold .6.1.Cold Slug Wells2.3.1.Venting2.3.4.5.Draft Angle1.Many different types of gates can be used such as pin, fan, tunnel, taband edge gates. Gate type should be selected based on location andpart geometry.Gate diameters equivalent to 50% of the average wall thickness arerecommendedLand lengths of 0.50mm–0.90mm (0.020"–0.035") are typically recommended.Avoid placing gates in thin regions of the part. It is best for material to flowfrom thick to thin regions in the part.Full-round runners or a modified trapezoid runner are the best designs.Half-round runners are not recommended due to excessive pressure drop.Only naturally balanced runner systems (“H” pattern) are recommended.Runner diameters larger than 3.8mm (0.150") and not exceeding 9.5mm(0.375") are recommended.Step each 90 bend in the system down in size (from sprue to gate)approximately 1.5mm (1/16") to reduce pressure drop.Place vents at each 90 intersection and vent to atmosphere.Hot runner molds are acceptable and should be sized by the manufacturer.Place these wells at the base of the sprue to capture the cold material firstemerging from the nozzle.Place wells at every 90 bend in the runner system.Well depths approximately 1.5 times the diameter of the runner provide thebest results.Place vents at the end of fill and anywhere potential knit/weld lineswill occur.All vents need to be vented to atmosphere.For circular parts, full perimeter venting is recommended.Cut vent depths to 0.013mm–0.025mm (0.0005"–0.001") and a land lengthof 4.0mm (0.160").Increase vent depth to 1.5mm (0.060") at 4.0mm (0.160") away from thecavity and vent to atmosphere.Maintain a minimum draft angle of 1 per side.Processing Guide3
Troubleshooting RecommendationsProblemCauseMelt and/or moldtoo coldIncomplete FillMold designSolution Increase nozzle and barrel temperaturesIncrease mold temperatureIncrease injection rateIncrease pack and hold pressureIncrease nozzle tip diameterCheck thermocouples and heater bands Enlarge or widen vents and increase number of ventsCheck that vents are unpluggedCheck that gates are unpluggedEnlarge gates and/or runnersPerform short shots to determine fill pattern andverify proper vent locationIncrease wall thickness to move gas trap toparting line BrittlenessShot size Increase shot sizeIncrease cushionDecrease transfer positionLow melttemperature Increase melt temperatureIncrease injection rateMeasure melt temperature with pyrometerDegraded/overheatedmaterial Decrease melt temperatureDecrease back pressureUse smaller barrel/excessive residence timeDecrease screw rpm Relocate gate to nonstress areaIncrease gate size to allow higher flow rate and lowermolded in stressMelt temperaturetoo low Increase melt temperatureIncrease mold temperatureIncrease injection speedIncrease screw rpmInsufficient packing Increase pack and hold pressure, and timeIncrease shot sizeIncrease gate sizeGate locationand/or sizeFibers on Surface(Splay)4Therma-Tech
Troubleshooting RecommendationsProblemSink MarksFlashExcessive ShrinkNot Enough ShrinkCauseSolutionPart geometrytoo thick Reduce wall thicknessReduce rib thicknessMaintain nominal wall thicknessMelt too hot Decrease nozzle and barrel temperaturesDecrease mold temperatureInsufficientmaterial volume Increase shot sizeIncrease injection rateIncrease pack pressure/timeIncrease gate sizeInjection pressuretoo high Decrease injection pressureIncrease clamp pressureDecrease injection rateIncrease transfer positionExcessmaterial volume Decrease pack pressureDecrease shot sizeDecrease injection rateMelt and/or moldtoo hot Decrease nozzle and barrel temperaturesDecrease mold temperatureDecrease screw speedToo muchorientation Increase packing time and pressureIncrease hold pressureDecrease melt temperatureDecrease mold temperatureDecrease injection speedDecrease screw rpmIncrease ventingIncrease cooling timeToo littleorientation Decrease packing pressure and timeDecrease hold pressureIncrease melt temperatureIncrease mold temperatureIncrease injection speedIncrease screw rpmDecrease cooling timeProcessing Guide5
Troubleshooting RecommendationsProblemBurningNozzle DroolCauseSolutionMelt and/or moldtoo cold Decrease nozzle and barrel temperaturesDecrease mold temperatureDecrease injection rateMold design Clean, widen and increase number of ventsIncrease gate size or number of gatesMoisture Verify material is dried at proper conditionsNozzle temperaturetoo hot Decrease nozzle temperatureDecrease back pressureIncrease screw decompressionVerify material has been dried at proper conditionsMelt front temperaturesare too low Increase pack and hold pressureIncrease melt temperatureIncrease vent width and locationsIncrease injection rateIncrease mold temperature Decrease injection rateIncrease gate sizePerform short shots to determine fill patternand verify proper vent locationAdd vents and/or false ejector pinMove gate locationExcessive orientation Increase cooling timeIncrease melt temperatureDecrease injection pressure and injection rateMold design Increase number of gatesCavities areoverpacked Decrease injection rate and pressureDecrease pack and hold pressureDecrease nozzle and barrel temperaturesDecrease mold temperatureIncrease cooling timeMold design Increase draft anglePart is too hot Decrease nozzle and barrel temperaturesDecrease mold temperatureIncrease cooling timeWeld LinesMold designWarpSticking in Mold6Therma-Tech
1.844.4AVIENTwww.avient.comCopyright 2020, Avient Corporation. Avient makes no representations, guarantees, or warranties of any kind with respect to the information contained in this document about its accuracy, suitabilityfor particular applications, or the results obtained or obtainable using the information. Some of the information arises from laboratory work with small-scale equipment which may not provide a reliableindication of performance or properties obtained or obtainable on larger-scale equipment. Values reported as “typical” or stated without a range do not state minimum or maximum properties; consult yoursales representative for property ranges and min/max specifications. Processing conditions can cause material properties to shift from the values stated in the information. Avient makes no warranties orguarantees respecting suitability of either Avient’s products or the information for your process or end-use application. You have the responsibility to conduct full-scale end-product performance testingto determine suitability in your application, and you assume all risk and liability arising from your use of the information and/or use or handling of any product. AVIENT MAKES NO WARRANTIES, EXPRESSOR IMPLIED, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, either with respect to the information or products reflected by theinformation. This literature shall NOT operate as permission, recommendation, or inducement to practice any patented invention without permission of the patent owner.
Injection Molding Parameters Base Resin PPA PPS PA 6/6 PA 12 Barrel Temperatures F ( C)* Rear Zone 550–580 . Injection Velocity 1.0–3.0 in/sec Back Pressure 25–100 psi Screw Speed 25–75 rpm Drying Parameters F ( C) 6 hours @ 175 (80) 6 hours @ 300 (150) 3 hours @ 180 (82) 3 hours @ 180 (82)
