A kind of thermosetting and water-based paint wet-on-wet type weld sealant and preparation method thereof

Abstract

The invention discloses thermosetting weld joint sealant matched with water paint under a wet-on-wet condition. The thermosetting weld joint sealant comprises components in percentage by mass as follows: 20-35% of PVC (polyvinyl chloride) resin, 20%-35% of a filling agent, 15%-25% of a plasticizer A, 5%-10% of a plasticizer B, 2%-5% of a dispersing agent, 1%-15% of a tackifier, 2%-10% of a moisture absorbent and 1%-5% of a stabilizer. A preparation method of the thermosetting weld joint sealant comprises steps as follows: (1), powder is added to the plasticizers and uniformly stirred until no particles exist, then the dispersing agent is added to the mixture for several times, and the mixture is stirred under vacuum; (2), the mixture is left to stand still until the product is cured; (3), the viscosity of the product is adjusted after curing; (4), the mixture is filtered through a filter screen, and the thermosetting low-temperature weld joint sealant is obtained. The weld joint sealant is mainly used for weld joint sealing between an inner plate connection part and an outer plate connection part of an automobile, and the adhesion, the shearing strength and the stretching strength are greatly improved; the thermosetting weld joint sealant can meet the requirement of customers for the wet-on-wet process with the water paint, drying channels are reduced, the requirement for temperature is reduced, the production efficiency of the customers is improved, and the energy consumption cost is reduced.

Description

technical field [0001] The invention relates to a weld seam sealant, in particular to a thermosetting and water-based paint wet-on-wet weld seam sealant acting between the joints of the inner panel and the outer panel of an automobile and a preparation method thereof. Background technique [0002] Generally speaking, the joints of the inner and outer plates of most automobile steel plates are coated with weld sealant to play the role of waterproof, anti-rust and noise reduction. Pre-drying→intermediate coating→finish paint completes the hardening reaction after oven baking, and the top paint used is oil-based paint. [0003] The original weld seam sealant is pre-dried → intermediate coating → topcoat three ovens. The topcoat used is oil-based paint. The oven time for each oven is 30 minutes, and the temperature is 140. The baking time is long and the efficiency is low. And oily paint solvents are generally chemical preparations, which are more harmful to the environment. I...

AI Technical Summary

Problems solved by technology

Since the main solvent of water-based paint is water, it is incompatible with lipid compounds, resulting in direct contact between the weld sealant and the water-based paint, and streaks appear on the surface of the water-based paint after drying, which is not smooth enough

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