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How to test the UV resistance of  PP yarn ? We need to understand the following steps:

1000D anti-ultraviolet polypropylene filament index: Strong 38N or more Elongation 30% or less Dry heat shrinkage within 8% @132oC/15mins

Anti-ultraviolet requirements: After 200 hours of UV treatment, the strength is maintained above 50% before irradiation; the elongation loss is less than 50%.

The details are as follows: one cycle: ultraviolet irradiation for 8 hours 60 ° C, condensation for 4 hours 50 ° C for 200 hours or 16.7 cycles

Example: Black 801 anti-UV data is as follows:

Before irradiation, after irradiation, percentage of strength retention, percentage loss of elongation

Strong N                       40.6                              41.6                           41.6/40.6 about 100%

Elongation %                25.2                              21.0                           (25.2-21.0)/25.2=16.6

Through the introduction, do you know how to carry out the UV resistance test of PP yarn ?