Flooring made of PVC
The best of two worlds
Polyvinyl chloride (PVC) remains one of the most cost-effective plastics on the market. It is also one of the most versatile, not least due to the fact that the characteristics of this material can be further enhanced in combination with other polymers.
For example, the ethylene vinyl acetate copolymer Levamelt® makes PVC softer and, at the same time, more resistant. Unlike many liquid plasticizers, the addition of Levamelt® results in lasting improvements in characteristics because this additive cannot be washed out of the polymer matrix. This also prevents surface contamination as a result of plasticizer migration.
Levamelt® grades with a vinyl acetate content of between 65 % and 80 % can be mixed with PVC in all possible ratios. This means that the Shore hardness of a PVC product can be controlled within a wide range by adding Levamelt®. In test mixtures, 30 % Levamelt® 600 in PVC resulted in hardnesses of approximately 55 Shore D, while the hardness with 50 % of this polymer additive was only around 23 Shore D. One notable side-effect is the significant improvement in surface quality. Levamelt® prevents the sticky feeling typical of plasticizers which other additives produce.
The hardnesses that can be achieved depend on the vinyl acetate content of the Levamelt® additive. The higher the VA content, the harder the blend. Thanks to the rubber-like elasticity of Levamelt®, the elongation at break is also improved by the addition of Levamelt®. In contrast, the low-temperature resistance of a PVC-Levamelt® blend (60:40) reduces as the VA content falls.
In terms of migration resistance and low fogging, Levamelt® is far superior as a PVC modifier both to the majority of liquid plasticizers and other polymer alternatives. Levamelt® even surpasses polyurethanes and nitrile rubbers in terms of resistance to weathering and thermal aging.
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