Causes and solutions for yellowing of polyurethane foam.
Yellowing in polyurethane foam can be attributed to various factors and falls into four main categories:
Yellowing in polyurethane foam can be attributed to various factors and falls into four main categories:
Polyurethane foam(PU foam) primarily consist of polyurethane as their main component. The raw materials primarily include polyisocyanates and polyols, with the addition of various additives, the most crucial of which are a series of foaming agents related to the foaming process.
The apparent hardness of polyurethane foam is predominantly shaped by the following elements:
In China, a foam density of around 50 is considered good, as anything over 50 likely contains additives that you might not want in your foam.
Within the industry, sponge foam is typically classified according to its density. In the market, you can commonly find two primary categories of sponge foam: high-density sponge foam and regular sponge foam. These two types are easily distinguishable by their appearance and texture.
Polyurethane synthesis and its associated materials generally employ two main categories of catalysts: tertiary amine catalysts and organometallic catalysts.