Antiblockingmittel und Verfahren zu dessen Herstellung

摘要

An anti-blocking agent comprising silica or mixtures of silica and zeolite is described, which is characterized in that it has a bimodal pore size distribution, the first maximum of the bidomal pore size distribution being in the pore size range < 5 nm and the second maximum of the bimodal pore size distribution in the pore size range > 6 nm. The anti-blocking agent is obtainable by micronizing a mixture comprising silica of a certain pore size and silica and/or zeolite having a different pore size. It can be produced together with slip agent as a combined anti-blocking and slip agent. Incorporation of the anti-blocking agent or of the combined anti-blocking and slip agent into a polymer in the form of a master batch is preferable. In addition to a better dispersion and distribution of the anti-blocking agent particles in films and the improved optical properties associated therewith, the particular advantage of the anti-blocking agent according to the invention is that the adsorption of slip agent is avoided or greatly reduced, so that less slip agent can be used than in the prior art.