Study on the application of yellow-resistant degassing wax in HAA powder coating

01 Foreword
curing agents of weather-resistant polyester powder coatings mainly use TGIC (Triglycidyl isocyanurate), chemically named isocyanate triglycerides. Polyester TGIC system technology mature, weather resistance is good, economy is good, curing window width, yellow resistance is good, there are many advantages. However, since its incention in 1998, the European Union believes that TGIC will cause questionable genetic variation, requiring polyester TGIC powder coatings to use toxic markings with skulls, leaving a wide range of powder coating users confused about the system's powder coatings

. China's Ministry of Industry and Information Technology formulated the "part of the industrial industry to eliminate backward production process equipment and product guidance catalog (2010 this)" chemical category Article 64 also listed "isocyanate-containing glycerides (TGIC) powder coatings", such provisions have also become hanging on the industry's head a sword.
as an alternative to TGIC, HAA (β-hydroxyamide) has the potential to develop with its low toxicity and environmentally friendly characteristics. The Ministry of Industry and Information Technology, the Ministry of Science and Technology and the Ministry of Environmental Protection have compiled the List of Alternatives to Toxic and Harmful Raw Materials (Products) Encouraged by the State (2016 Edition), which also includes HAA alternative TGIC in the promotion category. However, the polyester HAA system also has some disadvantages: polyester and HAA shrink reaction will continue to release H2O, the surface is easy to cause shrink holes and bubbles, the product is prone to yellowing, these shortcomings cause polyester / HAA system promotion difficulties.
As the most commonly used de-foaming agent, the sabbath can also help the polyester/HAA system de-foaming, but the sabbath itself will also bring yellowing problems, so finding a yellow-resistant degassing agent has become an important topic in the promotion of polyester HAA system.
02 Experimental Purpose
In order to study wax-based degassing agents that can be used in polyester HAA system, Tianshi wax powder and upstream and downstream enterprises work closely together to test the application effect of polyamide wax degassing agent NEW0405 in this formulation system based on HAA cured polyester resin SJ5122.
03 The experimental part3.1 Experimental formula
3.2 Experimental method
1, Determination of suitable dosage:
After several sets of formulation experiments, it can be seen that in the case of 120um coating basically no foam, the appropriate amount of sabbath fragrance is 0.3%, degassing agent NEW0405 suitable dosage is 0.8%, When used in the joint use of the sabbath fragrance and the degassing agent NEW0405, the scenting dose was 0.1%, and the degassing agent NEW-0405 was 0.6% and the total dosage was 0.7%.
2, yellow change situation comparison:
at the normal baking temperature of 200 degrees C x 10min, the yellow change index of formula 1-4 is measured with a color difference meter

3 experimental data
the addition of different degassing agent polyester HAA yellowing system data are as follows:
04 conclusion and analysis
polyamide wax degassing agent NEW0405 in the polyester HAA system can play a better degassing effect, and resting fragrance, degassing efficiency is slightly poor, need a higher amount of addition, but has a relatively good yellow resistance.