The production method of curable transparent yellowing-resistant base polyurethane prepolymer for use as
Technical field
The present invention relates to the macromolecule chemical industry field, especially a kind of production method of curable transparent yellowing-resistant base polyurethane prepolymer for use as.
Background technology
The adhesive solvent pollution problem is puzzlement glue production and a difficult problem of using enterprise always, and adopting solvent-free water-base resin or hot-melt resin is the prior development direction of present adhesive area.Moisture-curable polyurethane glue is because curing speed soon, does not use solvent, solidifies the rear high industries such as Furniture manufacture, automotive trim manufacture, adhesive bookbinding that are widely used in of bond strength.Moisture-curable polyurethane glue typically uses crystal type polyester and the synthetic polyurethane prepolymer that contains terminal isocyanate group of aromatic polyisocyanate, after applying glue, in the several seconds, relies on the physical crystal of polyester to produce initial grab; Along with open assembly time extends, isocyanate groups absorbs in air and the moisture on bur surface completes chain extending reaction, namely solidifies afterwards.But this type of glue is generally opaque or translucent solid, or by transparent, becomes opaquely after solidifying, and to transparent material is bonding, can produce inaesthetic glue trace; And light is to the transmission of transparent material, and the gluing place is xanthochromia gradually.Especially when bonding transparent material was used for decoration and packaging field, glue trace and xanthochromia were unacceptable.
Present manufacturing enterprise uses the bonding transparent material of hot melt adhesive that contains the TPO composition usually, can obtain the good transparency and anti-yellowing property, but the gluing temperature requirement of such glue easily causes the thermal change type of bonded material more than 140~180 ℃.Such tackiness agent softening temperature is 80 ℃ of left and right, also poor to base material sticking power simultaneously, is difficult to meet the requirements at the higher level of bonding strength, thermotolerance and weather resistance.
Summary of the invention
The objective of the invention is provides a kind of glue temperature significantly to reduce for the deficiency that solves above-mentioned technology, and performed polymer does not contain after solvent, nontoxic, tasteless and illumination the production method that is difficult for the curable transparent yellowing-resistant base polyurethane prepolymer for use as of xanthochromia.
the production method of the designed curable transparent yellowing-resistant base polyurethane prepolymer for use as of the present invention in order to achieve the above object, to with vacuum dewatering plant, thermometer, in the reactor of agitator and condensing works, drop into polyether glycol, castor oil polyhydric alcohol and liquid copolymeric polyester polyvalent alcohol, in vacuum tightness, be 0.07~0.08Mpa, temperature is under 120~130 ℃, to stir 2~3 hours, then add aliphatic isocyanates, temperature is down to 80 degrees centigrade, insulation reaction 2.5 hours, and then input organotin catalysts, continue reaction after 1 hour, be cooled to 60 degrees centigrade, then discharging sealing are preserved and are got final product, wherein:
Polyether glycol accounts for polyether glycol, castor oil polyhydric alcohol, liquid copolymeric polyester polyvalent alcohol, four kinds of 10-80% that drop into the material total amount of aliphatic isocyanates;
Castor oil polyhydric alcohol accounts for polyether glycol, castor oil polyhydric alcohol, liquid copolymeric polyester polyvalent alcohol, four kinds of 5-25% that drop into the material total amount of aliphatic isocyanates;
Aliphatic isocyanates accounts for polyether glycol, castor oil polyhydric alcohol, liquid copolymeric polyester polyvalent alcohol, four kinds of 5-40% that drop into the material total amount of aliphatic isocyanates;
All the other are liquid copolymerization polyester polyvalent alcohol, and liquid copolymerization polyester polyvalent alcohol accounts for polyether glycol, castor oil polyhydric alcohol, liquid copolymeric polyester polyvalent alcohol, four kinds of ratios that drop into the material total amount of aliphatic isocyanates more than or equal to 5%;
The organotin catalysts ratio is more than or equal to 0.1%.
Described polyether glycol is the multipolymer of polyoxyethylene glycol and polytetrahydrofuran, and polyether glycol accounts for polyether glycol, castor oil polyhydric alcohol, liquid copolymeric polyester polyvalent alcohol, four kinds of 20-70% that drop into the material total amount of aliphatic isocyanates.
The molecular weight of described castor oil polyhydric alcohol is 700, and castor oil polyhydric alcohol accounts for polyether glycol, castor oil polyhydric alcohol, liquid copolymeric polyester polyvalent alcohol, four kinds of 5-15% that drop into the material total amount of aliphatic isocyanates.
Described aliphatic isocyanates is l, one or both in hexamethylene-diisocyanate, isophorone diisocyanate, aliphatic isocyanates account for polyether glycol, castor oil polyhydric alcohol, liquid copolymeric polyester polyvalent alcohol, four kinds of 12-20% that drop into the material total amount of aliphatic isocyanates.
Described liquid copolymerization polyester polyvalent alcohol is obtained by method production once: in the reactor with vacuum dewatering plant, thermometer, agitator and condensing works, add hexanodioic acid, 2,4-diethyl-1, the 5-pentanediol, the 2-methyl isophthalic acid, the 8-ethohexadiol, wherein the mol ratio of two kinds of glycol can be 0.2~1.8; The mol ratio of glycol and hexanodioic acid can be 1.18~1.05; Catalyzer uses dibutyl tin laurate, and add-on is 0.08~0.1% of reaction-ure mixture, heats up and starts simultaneously to stir; When being warmed up to 190 ℃, start to distillate moisture, continue to be warming up to interior temperature and reach 220 ℃, while measuring acid number less than 15mg/KOH, start to reduce pressure to steam and react oligopolymer and the unnecessary alcohol that generates, when overhead product reduced or be slack-off, the high vacuum reaction was carried out in decompression, and system pressure remains on below 80Pa, in 3 hours reaction times, polycondensation finishes.Under nitrogen protection, remove the vacuum discharging and obtain liquid copolyester polyvalent alcohol.
The production method of the resulting curable transparent yellowing-resistant base polyurethane prepolymer for use as of the present invention, use polyether glycol, castor oil polyhydric alcohol and three kinds of polyol groups of liquid copolymeric polyester polyol and, and use aliphatic isocyanates synthesis of polyurethane prepolymer, this performed polymer is fully transparent after solidifying, owing to having avoided using polyisocyanates composition such as toluene two isocyanides that contain the phenyl ring composition, after gluing, glue-line is difficult for xanthochromia through illumination simultaneously.Used simultaneously the polyfunctionality compositions such as castor oil derivative, the performed polymer mechanical property is enhanced.This performed polymer does not contain solvent, nontoxic, tasteless; Use this performed polymer configuration moisture-curable polyurethane tackiness agent, best gluing temperature is at 70~90 ℃, various physical behaviors are identical with the coating process of polyolefin hot-melt, but therefore gluing temperature decrease produces initial strength faster than polyolefin hot-melt glue; After gluing, rely on colloid inside to exist in active isocyanate group and environment and adherend surface minute moisture reaction generation curing cross-linked, significantly improve the final bonding strength of glue.
Embodiment
The present invention is further described by the following embodiment.
Embodiment 1:
The production method of the curable transparent yellowing-resistant base polyurethane prepolymer for use as that the present embodiment is described, at first in the reactor that thermometer, agitator and condensing works are housed with vacuum dewatering plant, add hexanodioic acid 146.1g, 2,4-diethyl-1,5-pentanediol 80g, 2-methyl isophthalic acid, 8-ethohexadiol 90g, catalyzer dibutyl tin laurate 0.3g, heat up and start simultaneously to stir; When being warmed up to 190 ℃ of left and right, start to distillate moisture, continue to be warming up to interior temperature and reach 220 ℃, water to be distillated near theoretical amount the time, while measuring acid number less than 15mg/KOH, starting to reduce pressure steams oligopolymer and the unnecessary alcohol that reaction generates, when overhead product reduces or become unrestrained, the high vacuum reaction is carried out in decompression, system pressure remains on below 80Pa, and in 3 hours reaction times, polycondensation finishes.Under nitrogen protection, remove the vacuum discharging and obtain liquid copolyester polyvalent alcohol 1; With same method: in the reactor that thermometer, agitator and condensing works be housed of 500mL with vacuum dewatering plant, adding hexanodioic acid 146.1g, 2,4-diethyl-1,5-pentanediol 70g, the 2-methyl isophthalic acid, 8-ethohexadiol 100g, catalyzer dibutyl tin laurate 0.3g, heat up and start simultaneously to stir; When being warmed up to 190 ℃ of left and right, start to distillate moisture, continue to be warming up to interior temperature and reach 220 ℃, water to be distillated near theoretical amount the time, while measuring acid number less than 15mg/KOH, starting to reduce pressure steams oligopolymer and the unnecessary alcohol that reaction generates, when overhead product reduces or become unrestrained, the high vacuum reaction is carried out in decompression, system pressure remains on below 80Pa, and in 3 hours reaction times, polycondensation finishes.Under nitrogen protection, remove the vacuum discharging and obtain liquid copolyester polyvalent alcohol 2; And then to 500mL with in the reactor of vacuum dewatering plant, thermometer, agitator and condensing works, dropping into the 200g polyether glycol, the 35g castor oil polyhydric alcohol, 50g copolyester polyvalent alcohol 1,50g copolyester polyvalent alcohol 2 is that 0.07~0.08Mpa, temperature are to stir and dewatered 3 hours under 120~130 ℃ in vacuum tightness; Then the isophorone diisocyanate that adds 75g, 80 ℃, insulation reaction 2.5 hours; Then drop into 0.5g catalyzer dibutyl tin laurate and continue reaction after 1 hour, titration NCO, be cooled to 60 ℃, and discharging sealing are preserved and got final product.
Embodiment 2:
The production method of the curable transparent yellowing-resistant base polyurethane prepolymer for use as that the present embodiment is described, in the reactor with vacuum dewatering plant, thermometer, agitator and condensing works, drop into the 200g polyether glycol, the 45g castor oil polyhydric alcohol, 10g copolyester polyvalent alcohol 1,40g copolyester polyvalent alcohol 2 is that 0.07~0.08Mpa, temperature are to stir and dewatered 3 hours under 120~130 ℃ in vacuum tightness; Then the isophorone diisocyanate that adds 75g, 80 ℃, insulation reaction 2.5 hours; Then drop into 0.3g catalyzer dibutyl tin laurate and continue reaction after 1 hour, the titration nco value reaches design load, is cooled to 60 ℃, and discharging sealing are preserved and got final product.
Embodiment 3:
The production method of the curable transparent yellowing-resistant base polyurethane prepolymer for use as that the present embodiment is described, in reactor, drop into the 100g polyether glycol, the 5g castor oil polyhydric alcohol, 200g copolyester polyvalent alcohol 1 is that 0.07~0.08Mpa, temperature are to stir and dewatered 3 hours under 120~130 ℃ in vacuum tightness; Then add the 65g isophorone diisocyanate, 80 ℃ of insulation reaction 2.5 hours; Then drop into 0.3g catalyzer dibutyl tin laurate and continue reaction after 1 hour, the titration nco value reaches design load, is cooled to 60 ℃, and discharging sealing are preserved and got final product.
Embodiment 4:
The production method of the curable transparent yellowing-resistant base polyurethane prepolymer for use as that the present embodiment is described, in reactor, drop into the 200g polyether glycol, the 35g castor oil polyhydric alcohol, the liquid copolyester polyvalent alcohol 2 of 100g is that 0.07~0.08Mpa, temperature are to stir and dewatered 3 hours under 120~130 ℃ in vacuum tightness; Then the isophorone diisocyanate that adds 62g, temperature are down to 80 ℃, insulation reaction 2.5 hours; Then drop into 0.3g catalyzer dibutyl tin laurate and continue reaction after 1 hour, titration NCO, be cooled to 60 ℃, and discharging sealing are preserved and got final product.
Comparative Examples 1:
In reactor, drop into the commercially available poly-hexanodioic acid hexylene glycol ester of 100g, the poly-hexanodioic acid 1,2-PD ester that 55g is commercially available, the polyethylene glycol adipate that 96g is commercially available).In vacuum tightness, be that 0.07~0.08Mpa, temperature are to stir and dewatered 3 hours under 120~130 ℃; Then add 4 of 65g, and the 4-MDI (4,4-MDI), 70 ℃ of insulation reaction 2.5 hours; Then drop into 0.3g catalyzer dibutyl tin laurate continuation reaction and be cooled to 90 ℃ after 1 hour, discharging sealing are preserved.
Comparative Examples 2:
To dropping into the commercially available polyethylene glycol adipate of 100g in reactor, the polydiethylene glycol adipate that 55g is commercially available, the commercially available poly-hexanodioic acid of 96g-2-methyl isophthalic acid, ammediol ester).In vacuum tightness, be that 0.07~0.08Mpa, temperature are to stir and dewatered 3 hours under 120~130 ℃; Then add 4 of 65g, and the 4-MDI (4,4-MDI), 70 ℃ of insulation reaction 2.5 hours; Then drop into 0.3g catalyzer dibutyl tin laurate continuation reaction and be cooled to 90 ℃ after 1 hour, discharging sealing are preserved.
Table 1: performed polymer character
The bonding PVC sheet of 1:PVC
2: 0.5cm thickness masking after use solidifying, translucent or the 3=that turns white is fully transparent according to the complete opaque 2=of following standard evaluation: 1=
3: use and solidify rear 0.2cm thickness masking, be placed in outdoor visible light place 90 days, according to the translucent 3=of the yellow micro-Huang of opaque 2=of following standard evaluation: 1=transparent not yellowing fully
As can be seen from Table 1, the transparency that the performed polymer that is made by the method for the invention has had and anti-yellowing property, mechanical property close to by aromatic isocyanate (as 4,4-MDI), performed polymer molten state viscosity is lower simultaneously, and moisture-curable speed is relatively low, is convenient to use under low temperature.