One of the drawbacks of rubber toughening is the increase in viscosity, which cannot be tolerated in some injection methods. By using core shell elastomers as tougheners, the viscosity increase becomes minimal.
ALBIDUR® products consist of a reactive resin in which silicone elastomer particles of a defined size (0.1 – 3 μm) are finely distributed. The silicone elastomer particles have an organic shell structure comprising reactive groups. The toughening mechanism is the same as for reactive liquid rubbers; however, the rubber domains are already preformed and not built during the curing process.
The typical addition levels are 10 percent and result in a substantially improved toughness over a very broad temperature range, reduced shrink and no or minimal loss of modulus and Tg. Furthermore the fatigue performance of the composite parts is increased significantly.
In contrast to the ALBIPOX® products, unsaturated polyester resins and vinyl ester resins can also be modified with ALBIDUR® based on such resins