What is the impact of excessive addition of curing agent on the heat resistance of the resin?
Excessive addition of curing agents may have a negative impact on the heat resistance of the resin, including the following aspects:
1.Increased tendency for thermal decomposition: Excessive curing agent may lead to an increase in the thermal decomposition tendency of the resin. Excessive curing agent can cause over curing, increasing the residue of unreacted curing agent in the resin. These residues may decompose under high temperature conditions, producing volatile substances or causing resin decomposition, thereby reducing the thermal stability of the resin.
2.Increased thermal weight loss: Excessive curing agent may cause an increase in thermal weight loss of the resin. Excessive curing agent can cause an increase in unreacted curing agent residues in the resin, which may decompose or evaporate at high temperatures, leading to a loss of resin quality.
3.Reduced melting temperature: Excessive addition of curing agent may cause a decrease in the melting temperature of the resin. Overcuring causes the resin network structure to be too tight and rigid, reducing the mobility between resin molecules and leading to a decrease in the melting temperature of the resin.
4.Increase in size change: Excessive addition of curing agent may lead to an increase in size change of the resin. Overcuring causes the molecular network structure of the resin to become too tight. When the resin is heated, it may experience larger size changes, such as shrinkage or expansion, due to limited thermal expansion.
It should be noted that different types of resins and curing agents may have different effects on heat resistance. Therefore, when using curing agents, it is best to follow the recommended curing agent dosage range provided by the resin supplier and refer to relevant thermal performance test data to ensure that the resin has the required heat resistance performance. At the same time, conducting laboratory testing and evaluation can also help determine the optimal amount of curing agent added to meet the heat resistance requirements of specific applications.
——
