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Hydrophilic polyisocyanate coating crosslinking agent
2017-7-15 12:11:46
Hydrophilic polyisocyanate coating crosslinking agent
Poly (ethylene glycol) mixed monomethyl ether and HDI trimer were used to prepare hydrophilic polyisocyanate crosslinking agent. The effects of different hydrophilic surfactants on the hydrophilicity of modified polyisocyanate were investigated.
The results showed that the hydrophobic polyisocyanate crosslinking agent prepared by using polyethylene glycol mixed monomethyl ether with average molecular weight of 500 as the hydrophilic monomer and nNCO / nOH was 6B1 had better emulsifying effect.
In the environment-friendly coatings, the two-component waterborne polyurethane coating has attracted much attention due to the high performance of the solvent-based two-component polyurethane coating and the low VOC content of the aqueous coating, which has become a hot spot in the field of environmentally friendly coatings. The
The two-component aqueous polyurethane is mainly composed of the aqueous hydroxyl component (component A) and the polyisocyanate crosslinking agent (component B), and the selection of the appropriate B component is of great importance for the properties of the final film.
Crosslinking agents for two-component aqueous polyurethane coatings are classified into two types: unmodified polyisocyanates and modified hydrophilic polyisocyanates. Unmodified polyisocyanates are susceptible to phase separation due to difficulty in homogeneity with aqueous hydroxyl components, and their use in aqueous two-component systems is limited.
In order to solve the problem of the mixing of the crosslinking agent with the aqueous hydroxyl component, it is conceivable to modify the hydrophobic component to prepare the polyisocyanate containing the hydrophilic segment. However, the polyisocyanate component reacts easily with water, and it is thought that the preparation of hydrophilic polyisocyanates for a long time does not make sense, until the JacobsPB and the like have been broken.
He modified the HDI trimer with polyethylene glycol monomethyl ether to give a polyisocyanate crosslinker which can be dispersed inwater and which can be used after the crosslinker has been dispersed in water for a long period of time Hydrophilic polyisocyanate cross-linking agent has come in handy.
Chinese name: Diethyl toluene diamine(DETDA)
Diethyltoluenediamine Raw material ：
TDA industrial, Sichuan production
Ethylene (Et) polymer grade, Shanghai production
TEA industrial imports
Poly (ethylene glycol) mixed monomethyl ether and HDI trimer were used to prepare hydrophilic polyisocyanate crosslinking agent. The effects of different hydrophilic surfactants on the hydrophilicity of modified polyisocyanate were investigated.
The results showed that the hydrophobic polyisocyanate crosslinking agent prepared by using polyethylene glycol mixed monomethyl ether with average molecular weight of 500 as the hydrophilic monomer and nNCO / nOH was 6B1 had better emulsifying effect.
In the environment-friendly coatings, the two-component waterborne polyurethane coating has attracted much attention due to the high performance of the solvent-based two-component polyurethane coating and the low VOC content of the aqueous coating, which has become a hot spot in the field of environmentally friendly coatings. The
The two-component aqueous polyurethane is mainly composed of the aqueous hydroxyl component (component A) and the polyisocyanate crosslinking agent (component B), and the selection of the appropriate B component is of great importance for the properties of the final film.
Crosslinking agents for two-component aqueous polyurethane coatings are classified into two types: unmodified polyisocyanates and modified hydrophilic polyisocyanates. Unmodified polyisocyanates are susceptible to phase separation due to difficulty in homogeneity with aqueous hydroxyl components, and their use in aqueous two-component systems is limited.
In order to solve the problem of the mixing of the crosslinking agent with the aqueous hydroxyl component, it is conceivable to modify the hydrophobic component to prepare the polyisocyanate containing the hydrophilic segment. However, the polyisocyanate component reacts easily with water, and it is thought that the preparation of hydrophilic polyisocyanates for a long time does not make sense, until the JacobsPB and the like have been broken.
He modified the HDI trimer with polyethylene glycol monomethyl ether to give a polyisocyanate crosslinker which can be dispersed inwater and which can be used after the crosslinker has been dispersed in water for a long period of time Hydrophilic polyisocyanate cross-linking agent has come in handy.
Chinese name: Diethyl toluene diamine(DETDA)
Diethyltoluenediamine Raw material ：
TDA industrial, Sichuan production
Ethylene (Et) polymer grade, Shanghai production
TEA industrial imports
A reagent grade additives
Since then, domestic and foreign research on the hydrophobic modification of polyisocyanate gradually increased, mainly non-ionic modification of the main, but also for ionic modification, non-ionic and ionic compound modification reported. According to the literature, hexamethylene diisocyanate (HDI) trimer has a stable six-membered ring structure and high functionality, low viscosity, easy to disperse, suitable for hydrophilic modification.
In this experiment, the use of polyethylene glycol mixed monomethyl ether (PEGMM) instead of pure polyethylene glycol monomethyl ether to modify the HDI trimer, to obtain a more excellent performance of the hydrophilic Isocyanate crosslinking agent.
(DBF), chemically pure; nonionic surfactants (OP-10), nonionic surfactants (OP-10), nonionic surfactants (OP-10), nonionic surfactants (OP-10) , Chemical pure; aliphatic polyoxyethylene ether (AEO3), chemically pure; polyethylene glycol mixed monomethyl ether (PEGMM), industrial products (the above three substances must be added molecular sieve, storage for 1 week after use).
Laboratory equipment and detection equipment: Fourier transform infrared spectrometer (FT-IR), MB3000; GC97 series of gas chromatography.
Preparation method: A four-necked flask equipped with a stirrer, a thermometer, a reflux condenser and a dropping funnel was placed in a constant temperature oil bath, and an HDI trimer and a small amount of a catalyst DBTL were preliminarily added to the flask, heated to 60e, , According to nNCO / nOH 6B1, slowly dropping PEGMM, constant temperature reaction for some time, the determination of NCO content, such as reached the theoretical value, the termination of the reaction that is hydrophilic HDI trimer.
Characterization and analysis The molecular structure of raw materials and products was determined by Fourier transform infrared spectroscopy. The composition of polyethylene glycol mixed monomethyl ether was determined by gas chromatograph. The isocyanate content was determined by / di-n-butylamine method. Stability of the crosslinking agent: 2 mL of the emulsified product was added to the centrifuge tube and centrifuged at a high speed of 2000 r / min for 30 min to observe the emulsion stratification.
The polyethylene glycol mixed ether used in this experiment mainly contains four different molecular weights of PEGMM. The higher the relative molecular mass, the higher the content.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
Since then, domestic and foreign research on the hydrophobic modification of polyisocyanate gradually increased, mainly non-ionic modification of the main, but also for ionic modification, non-ionic and ionic compound modification reported. According to the literature, hexamethylene diisocyanate (HDI) trimer has a stable six-membered ring structure and high functionality, low viscosity, easy to disperse, suitable for hydrophilic modification.
In this experiment, the use of polyethylene glycol mixed monomethyl ether (PEGMM) instead of pure polyethylene glycol monomethyl ether to modify the HDI trimer, to obtain a more excellent performance of the hydrophilic Isocyanate crosslinking agent.
(DBF), chemically pure; nonionic surfactants (OP-10), nonionic surfactants (OP-10), nonionic surfactants (OP-10), nonionic surfactants (OP-10) , Chemical pure; aliphatic polyoxyethylene ether (AEO3), chemically pure; polyethylene glycol mixed monomethyl ether (PEGMM), industrial products (the above three substances must be added molecular sieve, storage for 1 week after use).
Laboratory equipment and detection equipment: Fourier transform infrared spectrometer (FT-IR), MB3000; GC97 series of gas chromatography.
Preparation method: A four-necked flask equipped with a stirrer, a thermometer, a reflux condenser and a dropping funnel was placed in a constant temperature oil bath, and an HDI trimer and a small amount of a catalyst DBTL were preliminarily added to the flask, heated to 60e, , According to nNCO / nOH 6B1, slowly dropping PEGMM, constant temperature reaction for some time, the determination of NCO content, such as reached the theoretical value, the termination of the reaction that is hydrophilic HDI trimer.
Characterization and analysis The molecular structure of raw materials and products was determined by Fourier transform infrared spectroscopy. The composition of polyethylene glycol mixed monomethyl ether was determined by gas chromatograph. The isocyanate content was determined by / di-n-butylamine method. Stability of the crosslinking agent: 2 mL of the emulsified product was added to the centrifuge tube and centrifuged at a high speed of 2000 r / min for 30 min to observe the emulsion stratification.
The polyethylene glycol mixed ether used in this experiment mainly contains four different molecular weights of PEGMM. The higher the relative molecular mass, the higher the content.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
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