During the foaming process, if the hardness of the hard foam is not enough, how to increase the hardness? In this regard, I have collected some solutions for your reference only.
1. The lower cost option is to add calcium carbonate
Add 20% calcium carbonate, above 500 mesh. This method will not have much impact on performance indicators, mainly because of its low cost.
2. Improve index
Appropriately increase the TDI index, increase the amount of water, and correspondingly reduce the amount of MC, which can also increase the hardness appropriately.
3. Increase the amount of catalyst or add other types of catalysts or modifying reagents
There are some catalysts:
① Increase the POP content to within 80%;
② Try adding some modified MDI appropriately;
③ Add some polyester to polyether;
④ Add some rigid foam polyether, and it may be better to choose a polyether with higher functionality;
⑤ Increase the proportion of hard foam expansion and cross-linking agents such as 405 and 403;
⑥ Add trimerization catalyst and increase the proportion of black and white materials.
4. Increase the density of raw materials
That is, when foaming, appropriately adjust the foaming ratio, reduce the foaming ratio, and increase the density.
5. Use a little pore opening agent appropriately
6. Increase the capacity of foam
7. Adding powder can also increase the hardness
