heat and chemical resistance resin-heat resistance HM type resin
Features and Application of heat resistance HM type resin
Executive Standard of heat resistance HM type resin: GB/T8237-2005
Gel Time (mins)
Heat resistance HM type resin, high strength and rigidity, suitable for medium heat resisting required product.
medium heat resisting required product.
Advantages and Disadvantages
On a broad scale of viscosity, vinyl esters are midway between polyesters and epoxy resins, before adding styrene. Thinning effects workability and strength - 'thinning' reduced strength but makes it easier to brush or spray.
Vinyl esters are more tolerant of stretching than polyesters. This makes them more able to absorb impact without damage. They are also less likely to show stress cracking.
Vinyl ester has fewer open sites in its molecular chain. This makes it much more resistant to water penetration ('hydrolysis') which can cause osmotic blistering. Vinyl esters shrink less on curing, which means that 'pre-release' of a laminate from a mold is less significant. Vinyl esters are more tolerant of stretching than polyesters. This makes them more able to absorb impact without damage. They are also less likely to show stress cracking.
The cross bonding of vinyl esters is superior to that of polyesters. This means that vinyl esters bond to core materials much more effectively than polyesters and delamination is less of an issue. Vinyl esters are less sensitive to ambient conditions (temperature and humidity) than are polyesters.
Vinyl esters are more expensive than polyesters through careful calculations are required to assess the cost impact of a significant build project such as a luxury yacht. This is because the relative strengths need to be factored in - you can use less vinyl ester to achieve a given strength.
Both resins are susceptible to 'chalking' - UV breakdown at the surface - unless an additive is incorporated into the mix.