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Various methods for increasing the hardness of polyurethane rigid foam
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發(fā)布日期:2024-05-22
In the foaming process, if the hardness of the hard bubble is not enough, how to improve the hardness?
In this regard, the following solutions are for your reference only.
1, lower cost preferred, add calcium carbonate
Add 20% calcium carbonate, 500 mesh or more. This method will not have much impact on the performance indicators, mainly because of the low cost.

2. Increase the index
Appropriately increase the TDI index, increase the water volume, and correspondingly reduce the amount of MC, which can also appropriately increase the hardness.

3, increase the amount of catalyst or increase other types of catalyst or modified reagents
There are some catalysts:
① Increase the content of POP, within 80% can be;
② Add some modified MDI to try;
③ Add some polyester to polyether;
④ Add some hard foam polyether, choose the polyether with large functional degree may have a better effect;
⑤ Increase the proportion of 405, 403 and other hard foam expansion and crosslinking agents;
Add trimerization catalyst, and increase the proportion of black and white material.

4, improve the density of raw materials
That is, when foaming, the appropriate foaming ratio is adjusted to reduce the foaming ratio and increase the density.

5, appropriate use of a little opening agent

6. Increase the foam capacity

7, adding powder can also increase hardness

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