Coating containing high DP crosslinking agent

Coating containing high DP crosslinking agent, a high DP amino resin coating system, will be more than one using the same structure, but low DP amino resin coatings system need shorter time to reach the specified crosslink density, so high DP crosslinking agent coating needs only a small number of catalysts or weak acid catalyst can achieve the same curing condition. The influence of molecular weight of coating is mainly on the scope of flexibility.

With high DP amino resin curing coating, containing a high percentage of amino - amino and fewer amino paint - keys. This type of crosslinked network structure, forming a good hardness of coatings, but may be brittle. Can sometimes by choosing a more flexible paint resins to compensation. But generally requires high flexibility needs haplotype amino resin for coating.

Polyester containing carboxyl groups can react with melamine - formaldehyde to produce useful thermosetting coating surface, its wide range of physical properties.

Many butyl etherification melamine - formaldehyde resin with commercial interests, first of all, the initial degree of polymerization (molecular weight), and alkoxy and hydroxyl methyl groups and the proportion of different amino hydrogen. These differences will affect the liquid viscosity, melamine with polyester compatibility and the curing speed of enamel.

Although since the crosslinking often make coating has greater hardness and chemical resistance, but elastic damage is very large. In order to make the polyester paint to get enough flexibility.

Liujia oxygen methyl melamine (HMMM), is a kind of completely hydroxyl methylation and completely methylated amino resin monomer. With butyl etherification melamine - formaldehyde, its hydroxyl groups with polyester resin crosslinking reaction when heated to generate no softening of solids. From nature, without acid catalyst, even time or temperature, also won't happen HMMM self crosslinking.

However, bulk HMMM at 150 ℃ and the presence of acid catalyst, the crosslinking reaction will happen. On the contrary, even in the absence of strong acid to exist, the traditional etherification melamine and urea formaldehyde resin with the increase of temperature, strong self crosslinking reaction will occur.




Chinese name: Diethyl toluene diamine(DETDA)

Diethyltoluenediamine packing： net weight 200KG/ galvanized iron drum (a small cabinet pallet loaded 16 tons), 1000KG/IB barrels (a small cabinet loaded 18 tons or 23 tons of ISOTANK).


Due to the amino resin as main film forming material used to make molecular got behind in a mesh structure, so interesting is the amino resin and paint resin copolycondensation reaction, a typical example is the paint on the hydroxy and amino resin resin alkoxy methyl ether (exchange) reaction.

Can imagine, in the microscopic world melamine molecular how (in M) with hydroxyl pull from different film forming polymer, and a three-dimensional network structure, network structure determines the performance of the paint film.

In the heat and the presence of acid catalyst (usually curing conditions), the crosslinking reactions happen quickly, connect all of the available hydroxyl in the paint.

When the polymer network structure formed, the liquidity of reactants on the decline, some hydroxyl not reflected off left. Generally exist in the coating than the ratio of the ideal of excessive amounts of amino resin, the rest of the alkoxy can attend does not react with other reactions or in film.

In the previously mentioned amino resin is easy to each other since the crosslinking reaction, the result is in the production of the molecular weight increased. These reactions also occurred in coating curing. So rather than a degree of amino resin from crosslinking is a negative factor, than get good durability, closely essential factors of polymer matrix.

All three types of functional groups in the amino resin crosslinking reaction, in strong acid catalysis, fully alkylated melamine resin coating, there is evidence that these reactions occurred in exchange after with coating resin ether.

Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd 

Diethyl toluene diamine(DETDA)  http://www.yaruichem.com