尼龙 PA66 日本东丽 CM3006 汽车配件 电器 热稳定 阻燃 塑料颗粒

模具塑料PA66 聚酰胺66或尼龙66

典型应用范围:

同PA6相比，PA66更广泛应用于汽车工业、仪器壳体以及其它需要有抗冲击性和高强度要求的产品。

注塑模工艺条件:

干燥处理：如果加工前材料是密封的，那么就没有必要干燥。如果储存容器被打开，那么建议在85C的热空气中干燥处理。如果湿度大于0.2%，还需要进行105C，12小时的真空干燥。

熔化温度：260~290C。对玻璃添加剂的产品为275~280C。熔化温度应避免高于300C。

模具温度：建议80C。模具温度将影响结晶度，而结晶度将影响产品的物理特性。对于

薄壁塑件，如果使用低于40C的模具温度，则塑件的结晶度将随着时间而变化，为了保持

塑件的几何稳定性，需要进行退火处理。

注射压力：通常在750~1250bar，取决于材料和产品设计。

注射速度：高速（对于增强型材料应稍低一些）。

流道和浇口:

由于PA66的凝固时间很短，浇口的位置非常重要。浇口孔径不要小于0.5*t

（这里t为塑件厚度）。如果使用热流道，浇口尺寸应比使用常规流道小一些，

因为热流道能够帮助阻止材料过早凝固。如果用潜入式浇口，浇口的小直径

应当是0.75mm。

化学和物理特性:

PA66在聚酰胺材料中有较高的熔点。它是一种半晶体-晶体材料。PA66在较高温度也能保持较强的强度和刚度。PA66在成型后仍然具有吸湿性，其程度主要取决于材料的组成、壁厚以及环境条件。在产品设计时，一定要考虑吸湿性对几何稳定性的影响。

为了提高PA66的机械特性，经常加入各种各样的改性剂。玻璃就是常见的添加剂，有时为了提高抗冲击性还加入合成橡胶，如EPDM和SBR等。

PA66的粘性较低，流动性很好（但不如PA6）。这个性质可以用来加工很薄的元件。

它的粘度对温度变化很敏感。PA66的收缩率在1%~2%之间，加入玻璃纤维添加剂可以将

收缩率降低到0.2%~1% 。收缩率在流程方向和与流程方向相垂直方向上的差异是较大的。

PA66对许多溶剂具有抗溶性，但对酸和其它一些氯化剂的抵抗力较弱。

PA 66

Generic Class

PA 66 (Polyamide 66, or Nylon 66, or poly (hexamethyleneadipamide))

Applications

Competes with PA 6 for most applications. PA 66 is heavily usedin the automotive industry, appliance housings, and generally whereimpact resistance and strength are required.

Injection Molding Processing conditions

Drying Drying is not required if the material is sealed prior tomolding; however, if the containers are left open, drying in a hotair oven at 85 C (185 F) is recommended. If the moisture content is> 0.2%, vacuum drying at 105 C (220 F) for 12 hours isrecommended.

Melt Temperature 260 - 290 C (500 - 554 F); 275 - 280 C (527 -536 F) for glass filled grades; melt temperatures above 300 C (572F) should be avoided

Mold Temperature 80 C (176 F) suggested. Mold temperatureaffects crystallinity level which in turn affects physicalproperties. In the case of thin walled parts, crystallinity changeswith time if mold temperatures of less than 40 C (104 F) are used.In such cases, annealing may be needed to retain dimensionalstability.

Resin Injection Pressure Generally between 750 - 1,250 bar(~11,000 - 18,000 psi), depends on material and product design

Injection Speed High (slightly lower for reinforced grades)

Runners and Gates

The gate location is important because of very fast freeze-offtimes. Any type of gate may be used; the aperture should not beless than half the thickness of the part. When hot runners areused, the size of the gates can be smaller than when cold runnersare used, because premature freeze-off is prevented. When usingsubmarine gates, the minimum diameter of the gate should be 0.75mm.

Chemical and physical properties

PA 66 homopolymer is produced by the polymerization ofhexamethylene diamine and adipic acid (a dibasic acid). Amongcommercially available polyamides, PA 66 has one of the highestmelting points. It is a

semicrystalline-crystalline material. The resins have strengthand stiffness which is retained at elevated temperatures. It doesabsorb moisture after molding, but the retention is not as much asin the case of PA 6. Moisture absorption depends on the compositionof the material, wall thickness, and environmental conditions.Dimensional stability and properties are all affected by the amountof moisture absorption which must be taken into account for productdesign.

Various modifiers are added to improve mechanical properties;glass is one of the most commonly used filler. Addition ofelastomers such as EPDM or SBR improves impact resistance.

The viscosity is low and therefore, it flows easily (but not aseasily as PA 6). This allows molding of thin components. Theviscosity is very sensitive to temperature. Shrinkage is of theorder of 0.01 - 0.02 mm/mm (1 - 2%). Addition of reinforcing glassfibers reduces the shrinkage to 0.2 - 1%. Differential shrinkage inthe flow and cross-flow directions is quite high. Mineral fillersyield more isotropic moldings. PA 66 is resistant to most solventsbut not to strong acids or oxidizing agents.

Major Manufacturers

BASF (Ultramid A), DuPont (Minlon - mineral reinforcedgrades; Zytel), Monsanto (Vydyne),DSM (Akulon).