PA6 is a milky white or slightly yellow transparent to opaque keratinous crystalline polymer, which can be freely colored, has good toughness, wear resistance, self-lubrication, low rigidity, low temperature resistance, bacteria resistance, slow burning, slow extinguishing from fire, dripping and bubbling, and excellent molding processability: it can be injection molded, blow molded, cast, sprayed, powder molded, machined, welded, and bonded. PA6 is the PA with the highest water absorption rate, with poor dimensional stability and affects electrical properties (breakdown voltage).

Introduction

Chemical formula

¡ª[NH¡ª(CH2)5¡ªCO]n¡ª

Chinese name

Polyamide 6, nylon 6

Description

The maximum operating temperature of PA6 can reach 180¡æ, which will drop to 160¡æ after adding impact modifier, and can be increased to 199¡æ with 15%-50% glass fiber reinforcement. Inorganic filling PA can increase its heat deformation temperature.

Chemical and physical properties

The chemical and physical properties of PA6 are very similar to those of PA66, however, it has a lower melting point and a wide process temperature range. Its impact resistance and solubility resistance are better than those of PA66, but its hygroscopicity is also stronger. Because many quality characteristics of plastic parts are affected by hygroscopicity, this should be fully considered when designing products using PA6. In order to improve the mechanical properties of PA6 plastic raw materials, various modifiers are often added. Glass is the most common additive, and sometimes synthetic rubbers such as EPDM and SBR are added to improve impact resistance. For products without additives, the shrinkage rate of PA6 is between 1% and 1.5%. The shrinkage rate of molding and assembly is mainly affected by the crystallinity and hygroscopicity of the material. The actual shrinkage is also a function of the part design, wall thickness and other process parameters

Injection molding

Drying

Drying: Since PA6 easily absorbs moisture, special attention should be paid to drying before processing. If the material is supplied in waterproof packaging, the container should be kept closed. If the humidity is greater than 0.2%, it is recommended to dry in hot air above 80¡ãC for 16 hours. If the material has been exposed to air for more than 8 hours, it is recommended to vacuum dry at 105¡ãC for more than 8 hours. Melting temperature: 230-280¡ãC, 250-280¡ãC for reinforced varieties. Mold temperature: 80-90¡ãC. Mold temperature significantly affects crystallinity, which in turn affects the mechanical properties of the plastic part. Crystallinity is important for structural parts, so a mold temperature of 80-90¡ãC is recommended. Higher mold temperatures are also recommended for thin-walled and long-flow plastic parts. Increasing mold temperature can increase the strength and stiffness of the plastic part, but it reduces toughness. If the wall thickness is greater than 3mm, it is recommended to use a low-temperature mold of 20-40¡æ. For glass fiber reinforced materials, the mold temperature should be greater than 80¡æ. Injection pressure: generally between 750-1250bar (depending on the material and product design) Injection speed: high speed (slightly lower for reinforced materials) Runner and gate: The solidification time of PA6 is very short, so the location of the gate is very important. The gate aperture should not be less than 0.5

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