News Details
Crosslinking agent for resin coating
2017-7-29 11:37:49
Crosslinking agent for resin coating
As a variety of resin crosslinking agent, it is generally divided into the following categories:
(1) single-group separation agent: ammonium chloride and ammonium sulfate. At present in the glue, is the most widely used crosslinking agent ammonium chloride and ammonium sulfate, because they are low cost, good water solubility, non-toxic, tasteless and convenient use, etc, for the amount of general (in solid ammonium chloride) of liquid resin is 0.2% ~ 2%, too much has no obvious effect.
(2) multi-component crosslinking agents: ammonium chloride and urea, ammonium chloride and ammonia, or ammonium chloride and six methylamine and urea mixtures.
Using multicomponent crosslinking agent has two purposes, one is in order to prolong the life time of the resin, especially in the summer, because the room temperature is higher, used alone (or ammonium sulfate, ammonium chloride of the resin applicable period often cannot meet the use requirement, so often use multicomponent crosslinking agent; Second, in order to be able to use in winter, if the normal temperature crosslinking method is adopted, to accelerate the crosslinking of resins, the combination of ammonium chloride and concentrated hydrochloric acid is often used, which can shorten the crosslinking time.
The properties of UF resin are summarized as follows:
(1) because of a large number of the hydroxymethyl and amide group, soluble in water, and have good adhesive performance and so on many kinds of base material use is very convenient, and can be used with a variety of other materials, very suitable for mass production of wood glue.
(2) at room temperature or above 100 ℃ can quickly crosslinking, and can use acidic catalyst to accelerate the crosslinking process, in order to shorten the production cycle.
Chinese name: Diethyl toluene diamine(DETDA)
Physical and chemical properties: light yellow transparent liquid, slightly soluble in water, soluble in alcohols, ethers, ketones and other polar organic solvents, and polyether, polyester polyol compatibility.
Density 1.022
Viscosity (20 ℃) ??mPa·ss290±10
Pour Point ℃-9
Boiling point of310°C
As a variety of resin crosslinking agent, it is generally divided into the following categories:
(1) single-group separation agent: ammonium chloride and ammonium sulfate. At present in the glue, is the most widely used crosslinking agent ammonium chloride and ammonium sulfate, because they are low cost, good water solubility, non-toxic, tasteless and convenient use, etc, for the amount of general (in solid ammonium chloride) of liquid resin is 0.2% ~ 2%, too much has no obvious effect.
(2) multi-component crosslinking agents: ammonium chloride and urea, ammonium chloride and ammonia, or ammonium chloride and six methylamine and urea mixtures.
Using multicomponent crosslinking agent has two purposes, one is in order to prolong the life time of the resin, especially in the summer, because the room temperature is higher, used alone (or ammonium sulfate, ammonium chloride of the resin applicable period often cannot meet the use requirement, so often use multicomponent crosslinking agent; Second, in order to be able to use in winter, if the normal temperature crosslinking method is adopted, to accelerate the crosslinking of resins, the combination of ammonium chloride and concentrated hydrochloric acid is often used, which can shorten the crosslinking time.
The properties of UF resin are summarized as follows:
(1) because of a large number of the hydroxymethyl and amide group, soluble in water, and have good adhesive performance and so on many kinds of base material use is very convenient, and can be used with a variety of other materials, very suitable for mass production of wood glue.
(2) at room temperature or above 100 ℃ can quickly crosslinking, and can use acidic catalyst to accelerate the crosslinking process, in order to shorten the production cycle.
Chinese name: Diethyl toluene diamine(DETDA)
Physical and chemical properties: light yellow transparent liquid, slightly soluble in water, soluble in alcohols, ethers, ketones and other polar organic solvents, and polyether, polyester polyol compatibility.
Density 1.022
Viscosity (20 ℃) ??mPa·ss290±10
Pour Point ℃-9
Boiling point of310°C
Flash Point°C161.1°C
(3) UF resin has no color, no contamination of adhesive products, and dyes and pigments can be colored arbitrarily.
(4) good solvent resistance, high hardness and good heat resistance.
(5) adhesion strength ratio, plant glue height.
(6) the toxicity is small, but the crosslinking will release the irritating formaldehyde.
(7) it is easy to make and cheap.
(8) good light resistance and aging resistance.
(9) good technology and convenient use.
(10) brittle large, the crosslinking process can produce internal stress and crack.
(11) water-resistant and adhesion strength is lower than phenolic resin adhesive.
The traditional theory holds that UF resins are mainly polydispersible polymers which are produced by substituting urea and methylene or a small number of dimethyl chains before they are cross-linked. When crosslinking, the active groups in the resin (-ch2oh, -nh, -ch2-o-ch2 -) form a three-dimensional space structure between or with formaldehyde. It is generally believed that the crosslinking process of resin is a continuous process, and the adhesion strength increases with the extension of the crosslinking time.
However, Chow and Kollmann associates method reported the abnormal phenomenon in the process of UF resin crosslinking: namely resin crosslinking process Not happen in a row, the adhesive strength is increased, at the beginning of the bonding strength decrease in the agreed upon period of time, after then to revert to a balance state of strength. In the 1980s, the American academic community put forward a new theory about the cross-linking mechanism of UF resin.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
(3) UF resin has no color, no contamination of adhesive products, and dyes and pigments can be colored arbitrarily.
(4) good solvent resistance, high hardness and good heat resistance.
(5) adhesion strength ratio, plant glue height.
(6) the toxicity is small, but the crosslinking will release the irritating formaldehyde.
(7) it is easy to make and cheap.
(8) good light resistance and aging resistance.
(9) good technology and convenient use.
(10) brittle large, the crosslinking process can produce internal stress and crack.
(11) water-resistant and adhesion strength is lower than phenolic resin adhesive.
The traditional theory holds that UF resins are mainly polydispersible polymers which are produced by substituting urea and methylene or a small number of dimethyl chains before they are cross-linked. When crosslinking, the active groups in the resin (-ch2oh, -nh, -ch2-o-ch2 -) form a three-dimensional space structure between or with formaldehyde. It is generally believed that the crosslinking process of resin is a continuous process, and the adhesion strength increases with the extension of the crosslinking time.
However, Chow and Kollmann associates method reported the abnormal phenomenon in the process of UF resin crosslinking: namely resin crosslinking process Not happen in a row, the adhesive strength is increased, at the beginning of the bonding strength decrease in the agreed upon period of time, after then to revert to a balance state of strength. In the 1980s, the American academic community put forward a new theory about the cross-linking mechanism of UF resin.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
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