|发布时间:2019-08-05 10:38:31 | 浏览次数：|
1、吸湿性 Moisture absorption
刚顶出的注塑制品几乎不含水分。这点对于塑件以后的应用很重要，因为FRIANYL®-尼龙只在水分含量为大约1.5 – 2.5 %时，各项机械性能达到最佳。因此，注塑制品都需要调湿。
Injection mouldings that are ejected out of the mould have almost no moisture content. This is very important to recognize this for future applications for the moulding. FRIANYL®-polyamides only
attain their optimum mechanical properties after moisture equilibrium has been reached at about 1.5-2.5%. For this reason the injection mouldings should always be conditioned.
Moisture absorption depends on the crystallinity. Amorphous areas absorb moisture faster. That's why one should aim for an even crystallinity, which is achieved by the processing parameters.
The rate of moisture absorption is dependent on the FRIANYL®-types, the environmental conditions,and the wall thickness of the mouldings.
See attached conditioning table
It has to be noticed, that with a 1% increase in water content in the moulding it's volume increases by about 0.05-0.2%. This is of special significance for mouldings with tight dimensional tolerances.
2、饱和吸水率 Water absorption-saturated
The saturated water absorption of FRIANYL®-polyamides depends mainly on the material type and ranges as a rule is between 7-9%. The speed with which this happens depends, too on the wall thickness and the water temperature.
See attached conditioning table.
Conditioning table for FRIANYL® Polyamides
① ISO – 1110 规定的NK 23/50 条件下的标准调湿条件。
According to ISO-1110 for the conditioning of standard test bodies to the standard moisture content in NK 23/50 Conditioning time in hours/days for the adjustment of the water content equilibrium in normal humid air when stored for flat parts (plates) in FRIANYL®.
The water delivery process is subject to the same physical rules as the water absorption. This means that for practical purposes climate- and weather variations can be neglected because water absorption and - delivery do at least at room temperature and normal climate happen very slowly.
Increase of volume has to be taken into consideration see point 1 also concerning the water absorption.
3、测试水分含量 Determination of the moisture and water content
For the manufacturer it is sufficient to determine the moisture content in PA parts by establishing the increase in weight simply by weighing the parts before and after conditioning. Further more precise measurement methods are infrared drying and Karl-Fischer-Titration (KT-Titration), which is the usual method in labs.
The purpose of conditioning is to impart in the moulding whilst still in the moulding company the properties that the part will require later.
FRIANYL®-尼龙在水分含量1.5 – 2.5 %时达到其特定的性能。因为调湿过程，随不同工艺，要花费时间和成本。客户需要针对特定应用，在调湿之前要考虑是不是有必要。
FRIANYL®-polyamides attain their specific property values with a moisture content of 1.5-2.5%.Because the conditioning process is, depending upon the chosen procedure, expensive and timeconsuming,one should first consider whether a particular case really requires conditioning.
Should one decide in favour of conditioning then there are several options available which can be selected for different reasons:
塑件封入PE 包装袋，添加2-5% 的水分
Packing in PE-bags with the addition of 2-5% Water
Defined storage time at room temperature and normal environment moisture
Storage in warm water directly at the injection moulding machine
With special conditioning devices, which are available on the market
Purpose built conditioning chambers with steam or tropical climate
A prerequisite for controlled conditioning of mouldings is the supervision of the moisture content andestablishing the conditioning time.