Heat-curable rubber compositions with plastisol-like rheology

Abstract

The invention relates to heat-curing reactive compositions based on natural and / or synthetic liquid elastomers containing olefinic double bonds and on vulcanizing agents, where these comprise a quantity, relative to the entire composition, of from 1 to 25 % by weight, preferably from 1 to 15 % by weight, of at least one liquid polyisoprene, preferably at least one cis-1,4 polyisoprene; a quantity, relative to the entire composition, of from 0.5 to 10 % by weight, preferably from 0.5 to 5 % by weight, of at least one functionalized liquid polybutadiene; a quantity, relative to the entire composition, of up to 40 % by weight, preferably from 1 to 25 % by weight, of a triglyceride fraction, the distribution of fatty acid in which comprises a proportion of at least 5 % by weight, more particularly at least 60 % by weight, of one or more [omega]-3 fatty acids and / or one or more omega-6 fatty acids; and at least one vulcanizing agent, where the proportion, relative to the entire composition, of synthetic polymers having at least one C=C double bond and / or at least one C=C triple bond is at least 7.5 % by weight, preferably 9 % by weight. These have plastisol-like rheology and therefore can be applied at room temperature by conventional spray systems. The invention also relates to use of same as sealant composition or as coating composition, and to methods for bonding components and / or sealing joints between components and / or coating components with use of the compositions.

Description

technical field [0001] The present invention relates to thermosetting compositions based on liquid rubber with plastisol-like rheological properties, to their use in the field of automotive paint and to their use in vehicle paint shops for painting A method of cloth, sealing or bonding a component. Background technique [0002] Coating or sealing of sheet metal parts (parts) in vehicle structures—especially sheet metal parts on automobile bodies—is often performed on sheet metal parts coated with cationic electrophoretic paint (KTL, cataphoretic paint) Carried on. The seam sealing and coating compounds used in this method are later cured in a paint drying oven. Before that, the parts to be bonded or sealed are passed through stages of cleaning, phosphating and dip prime coating. The treatments used in these stages allow the adhesive or sealant to be washed out of the bonded joint. To meet these requirements, various methods are becoming known, such as thermal / inductive p...

AI Technical Summary

Problems solved by technology

Also, cured plastisols have thermoplastic properties, i.e. their strength is greatly restricted at high temperatures, so they cannot be used for structural adhesive bonding

[0006] Another serious disadvantage of increasing importance is that commonly used plastisols are based on plasticizers which do not crosslink with the polymer matrix and are therefore expelled from the composition over a longer period of time

Another disadvantage is the higher cost of such formulations

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