News Details
Crosslinking agent for thermosetting resin coating
2017-8-12 12:13:24
Crosslinking agent for thermosetting resin coating
Thermosetting resin coating crosslinking agent is an essential part of thermosetting resin crosslinking reaction agent for epoxy resin are kinds of itself, and crosslinking agent varieties more, only with epoxy resin and thermosetting resin crosslinking agent by combining different varieties of the two kinds of materials can be different the way of application and performance of different crosslinking products, this is one of the features of epoxy resin applications.
A new solution for the mixture ratio of epoxy resin and crosslinking agent
In theory, one epoxy and one amine hydrogen ratio, in fact, would normally be a little more than epoxy biamines, about 1.2 to 1. This is the principle.
Examples: epoxy-e - 44, epoxy, 0.44, solid content: 70%, crosslinked amine value 240, solid content 60%
Epoxy-equivalent = 100/0.44 = 227.3, amine-hydrogen equivalent = 56,000/240 = 233.3, that should be this ratio, 227.3/0.7:233.3/0.6 = 324.7:388.8? Non-reactive diluents.
For synthetic polyurethane, everyone knows that all of its ingredients are easy to absorb. During the operation, water is often accidentally entered, so the process of degassing is necessary. Small samples can easily absorb a certain amount of moisture that is not conducive to synthesis, so it should take off before any isocyanate reaction in the laboratory. Degassing can be removed by mixing the air. Degassing or drying processes are used in the following formula.
The most common hydrogen donor in polyurethane production is amines and alcohols. When the final product is elastomer, the commonly used chain extender is diamine and diol. Table 2 shows the reaction rate of various amino and hydroxy and phenyl isocyanates. The relative reaction velocity can be selected by the catalyst (see vulcanization time and the catalyst part).
Although "one-step" production of polyurethane elastomers has its advantages (e.g. low cost and fast speed), in most cases, people are willing to choose the "pre-polymerization" route.
The use of prepolymers is beneficial in some production. Although it is more expensive to buy the prepolymer than it is, it can avoid the evaporation of isocyanates during the operation. If prepared to synthesize prepolymers, the following typical procedures are helpful.
Heating 690g (1.38 equivalent) Terathane? 1000 polyether, under 90 ℃, vacuum mixing 1 ~ 2 hours, remove the existing moisture. Under nitrogen protection cooling to 70 ℃. Add 435g (3.5 equivalent) pure MDI.
Heat of reaction makes the temperature rise to 80 + 4 ℃, keep the temperature of 1 ~ 2 hours, to ensure that the reaction completely. In the absence of moisture, the pre-polymer produced by this technique can be stored at room temperature for months.
Chinese name: Diethyl toluene diamine(DETDA)
Chinese alias: aryl, aryl diethyl - aryl - methyl-p-phenylenediamine
English name: Benzenediamine, ar, ar-diethyl-ar-methyl-English aliases:Diethyltoluenediamine; ar, ar-Diethyl-ar-methylbenzenediamine;Diethylmethylbenzenediamine;
CAS No. :68479-98-1
EINECS No. :270 -877-4
Molecular formula: C11H18N2
Molecular Weight: 178.28
Boiling point: 310 ℃
Refractive index: 1.581
Flash Point: > 140 ℃
Inchi: InChI = 1/C11H18N2/c1-4-8-6-7 (3) 10 (12) 11 (13) 9 (8) 5-2/h6H ,4-5,12-13H2 ,1-3H3 density : 1.022
Risk Codes: R10; R35
RIDADR: UN 3082
Safety instructions: S2; S26; S39; S61
Packing Group: III
Thermosetting resin coating crosslinking agent is an essential part of thermosetting resin crosslinking reaction agent for epoxy resin are kinds of itself, and crosslinking agent varieties more, only with epoxy resin and thermosetting resin crosslinking agent by combining different varieties of the two kinds of materials can be different the way of application and performance of different crosslinking products, this is one of the features of epoxy resin applications.
A new solution for the mixture ratio of epoxy resin and crosslinking agent
In theory, one epoxy and one amine hydrogen ratio, in fact, would normally be a little more than epoxy biamines, about 1.2 to 1. This is the principle.
Examples: epoxy-e - 44, epoxy, 0.44, solid content: 70%, crosslinked amine value 240, solid content 60%
Epoxy-equivalent = 100/0.44 = 227.3, amine-hydrogen equivalent = 56,000/240 = 233.3, that should be this ratio, 227.3/0.7:233.3/0.6 = 324.7:388.8? Non-reactive diluents.
For synthetic polyurethane, everyone knows that all of its ingredients are easy to absorb. During the operation, water is often accidentally entered, so the process of degassing is necessary. Small samples can easily absorb a certain amount of moisture that is not conducive to synthesis, so it should take off before any isocyanate reaction in the laboratory. Degassing can be removed by mixing the air. Degassing or drying processes are used in the following formula.
The most common hydrogen donor in polyurethane production is amines and alcohols. When the final product is elastomer, the commonly used chain extender is diamine and diol. Table 2 shows the reaction rate of various amino and hydroxy and phenyl isocyanates. The relative reaction velocity can be selected by the catalyst (see vulcanization time and the catalyst part).
Although "one-step" production of polyurethane elastomers has its advantages (e.g. low cost and fast speed), in most cases, people are willing to choose the "pre-polymerization" route.
The use of prepolymers is beneficial in some production. Although it is more expensive to buy the prepolymer than it is, it can avoid the evaporation of isocyanates during the operation. If prepared to synthesize prepolymers, the following typical procedures are helpful.
Heating 690g (1.38 equivalent) Terathane? 1000 polyether, under 90 ℃, vacuum mixing 1 ~ 2 hours, remove the existing moisture. Under nitrogen protection cooling to 70 ℃. Add 435g (3.5 equivalent) pure MDI.
Heat of reaction makes the temperature rise to 80 + 4 ℃, keep the temperature of 1 ~ 2 hours, to ensure that the reaction completely. In the absence of moisture, the pre-polymer produced by this technique can be stored at room temperature for months.
Chinese name: Diethyl toluene diamine(DETDA)
Chinese alias: aryl, aryl diethyl - aryl - methyl-p-phenylenediamine
English name: Benzenediamine, ar, ar-diethyl-ar-methyl-English aliases:Diethyltoluenediamine; ar, ar-Diethyl-ar-methylbenzenediamine;Diethylmethylbenzenediamine;
CAS No. :68479-98-1
EINECS No. :270 -877-4
Molecular formula: C11H18N2
Molecular Weight: 178.28
Boiling point: 310 ℃
Refractive index: 1.581
Flash Point: > 140 ℃
Inchi: InChI = 1/C11H18N2/c1-4-8-6-7 (3) 10 (12) 11 (13) 9 (8) 5-2/h6H ,4-5,12-13H2 ,1-3H3 density : 1.022
Risk Codes: R10; R35
RIDADR: UN 3082
Safety instructions: S2; S26; S39; S61
Packing Group: III
Hazard Class: 6.1
TDI system performed system are usually prepared at low temperature, TDI in 40 ~ 45 ℃, Terathane? In its usual storage temperature 60 ~ 70 ℃ is more appropriate.
In order to obtain the best results, the content of isocyanates should be determined. The general procedure is as follows:
(1) take 3.5 ~ 6.5 g prepolymer and put it in a dry flask
(2) use the pipette to add 20mL dibutyl amine solution (338ml dibutyl amine in the volumetric flask to be diluted to 1000ml with dried toluene).
(3) add 50mL dried tetrahydrofuran
(4) stir to the average
(5) add 100mL of anhydrous isopropyl alcohol
(6) using 0.5 ml bromophenol blue solution as indicator, with 1.0 N hydrochloric acid solution titration to yellow end (0.1 g bromophenol blue, plus 1 N 1.5 ml NaOH solution, diluted with distilled water to 1000 ml).
(7) do a blank test, then calculate % NCO = (mLHCl blank - mLHCl sample)/sample weight x 4.2
In the above formulation, the NCO content of the prepolymer is about 7.75%.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
TDI system performed system are usually prepared at low temperature, TDI in 40 ~ 45 ℃, Terathane? In its usual storage temperature 60 ~ 70 ℃ is more appropriate.
In order to obtain the best results, the content of isocyanates should be determined. The general procedure is as follows:
(1) take 3.5 ~ 6.5 g prepolymer and put it in a dry flask
(2) use the pipette to add 20mL dibutyl amine solution (338ml dibutyl amine in the volumetric flask to be diluted to 1000ml with dried toluene).
(3) add 50mL dried tetrahydrofuran
(4) stir to the average
(5) add 100mL of anhydrous isopropyl alcohol
(6) using 0.5 ml bromophenol blue solution as indicator, with 1.0 N hydrochloric acid solution titration to yellow end (0.1 g bromophenol blue, plus 1 N 1.5 ml NaOH solution, diluted with distilled water to 1000 ml).
(7) do a blank test, then calculate % NCO = (mLHCl blank - mLHCl sample)/sample weight x 4.2
In the above formulation, the NCO content of the prepolymer is about 7.75%.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
Spanish
French
Italian
Portuguese
Japanese
Korean
Arabic
Russian