Low pressure molding

Property	Thermelt 867	Thermelt 858	Thermelt 195	Thermelt 865
Attributes	For Automotive application Versatile with broad process UL94: V0	UV Resistance High Hardness & Cohesion UL94: V0	Industrial application High Strength & Hardness UL94: V2	Excellent adhesion Brittle resistance @ low temp UL94: V0
Material	Polyamide	Polyamide	Polyamide	Polyamide
Appearance	Black	Black	Natural	Black
Shelf Life (months)	12	18	18	18
Physical Properties
Operating Range (°C)	-40/+150	-40/+150	-20/+170	-55/+120
Melt temperature range (°C)	220/230	210/230	210/230	190/210
Softening point (°C)	175-190	175-185	197-204	149-165
Brookfield viscosity	3.0-4.0 @220	4.0-6.0 @220	4.0-5.0 @232	2.5-3.5 @210
Mechanical Properties
Tensile strength (MPa)	6.1	8.1	13.2	3.0
Young Modulus	83	90	240	32
Elongation (%)	>200	340	580	>200
Shore hardness (D)	45	49	56	31
Moisture absorption (%)	2.8	1.9	1.2	3.0
Electrical Properties
Resistivity (Ω·cm)	2.9×10¹²	1.4×10¹¹	1×10¹¹	2.8×10¹¹
Dielectric rigidity (kV/mm)	20	20	19	18
Permittivity	5.6	5.6	ND	5.7
Thermal Properties
Vicat temperature (°C)	63	77	88	31
Glass transition (°C)	-50	-35	-35	-50
UL94 flammability	V0	V0	V2	V0

Frequently Asked Questions

Frequently Asked Questions Low-Pressure Molding (LPM)

What is Low Pressure Molding (LPM)?

Our is a hot-melt polyamide thermoplastic resin used in low-pressure molding to encapsulate and protect electronic components such as connectors, PCBs, and cables.

Does Thermelt absorb moisture?

Yes. Thermelt polyamide materials are moisture-sensitive and absorb humidity from the air, so proper storage and drying are required.

What does “processing moisture content <0.2%” mean?

It means Thermelt material must be kept extremely dry (less than 0.2% moisture) before processing, as excess moisture can cause bubbles, poor surface quality, and reduced mechanical performance during low pressure molding.

What is the minimum tolerance that Thermelt materials can hold?

Thermelt materials shrink 1 to 2% depending on the grade. This must be taken into account for critical applications.

Can material be regrind and reused?

Our LPM is a thermoplastic and can be remelted; however, we do not provide official approval or recommended regrind percentages, and any use of regrind is the responsibility of the user to validate.

What happens if moisture is not controlled?

Excess moisture can affect processing quality, so Thermelt must be kept sealed and processed with low moisture content (typically <0.2%).

How long is a typical injection cycle?

The molding cycle is dependent on the size and material section thickness of the component. Typical cycle time ranges from 90 seconds. Its thermoplastic properties enable it to set rapidly, unlike potting compounds.

What is a typical injection temperature for these materials?

Melt temperature ranges from 180°C to 230°C. Depending on mold-set design, this typically corresponds to cavity (mold) temperatures of 20°C to 60°C.

Learn More

A low-pressure molding (LPM) process is an encapsulation technique that protects sensitive electronic assemblies by injecting thermoplastic materials at controlled low pressure and temperature. This approach enables reliable sealing without damaging delicate components such as PCBs, connectors, and sensors.

Low Pressure Molding Process Flow

The LPM process transforms unprotected electronic components into fully encapsulated assemblies through a controlled sequence of material injection, molding, and solidification. Its low-pressure nature ensures mechanical integrity and minimizes stress on sensitive components.

Step 1: Component Placement

Electronic components are positioned within a custom mold cavity designed to match the final geometry.