CN110229317A - UV curable unsaturated polyester resin of high-vinyl degree of functionality and the preparation method and application thereof - Google Patents

Abstract

The invention discloses UV curable unsaturated polyester resins of high-vinyl degree of functionality and the preparation method and application thereof.The preparation method is under nitrogen protection, by acid anhydrides, epoxide, catalysts and solvents, to stir and be heated to 90~120 DEG C and keep the temperature 1-3h；Then solubilization has the vinyl glycidyl ether of polymerization inhibitor dropwise in 1-2h, ring opening copolymer reacts 4-6h at 90~120 DEG C, reaction system acid value is measured to 15mg KOH/g hereinafter, the unreacted monomer of vacuum distillation removing and solvent, obtain light yellow clear unsaturated polyester (UP).Preparation method of the invention is simple, the UV curable unsaturated polyester resin of prepared high-vinyl degree of functionality, and vinyl functionality is high, and solid content is up to 85% or more, and viscosity is 2000~6000mPas.Using the polyester preparation UV it is coating material solidified cost is relatively low, film have excellent glossiness and resistance to medium.

Description

UV-curable unsaturated polyester resin with high vinyl functionality and its preparation method and application

technical field

The invention relates to a polyester resin, in particular to an ultraviolet-curable unsaturated polyester resin and a preparation method and application thereof, belonging to the field of fine chemicals.

Background technique

UV curable coating means that UV light irradiation makes the photoinitiator crack into free radicals or anions and cations, further triggers the polymerization reaction of monomers containing active groups, and polymerizes into an insoluble and infusible solid coating film. Compared with traditional curing technology, UV curing technology saves energy, has fast curing speed, good coating performance, and is suitable for large-scale industrial production. The preparation of commonly used polyester acrylate is to introduce acrylic acid into the polyester chain through esterification reaction on the molecular chain of hydroxyl polyester resin, which requires an esterification reaction at 160-200 ° C. As a dehydration solvent, benzene and its homologues are poisonous , not easily removed from the resin. For example, the Chinese invention patent application CN105061738A undergoes a polycondensation reaction of terephthalic acid, 2,2,4,4-tetramethyl-1,3-cyclobutanediol and ethylene glycol under the action of a catalyst, and the reaction temperature is 200- 260°C to obtain a polycondensation product, and then add acrylic acid or acrylate to the above-mentioned reacted system to react to obtain a polyester-type acrylic UV-curable monomer. Chinese invention patent application CN105504245A first prepares carboxyl-containing polyester resin, and its esterification reaction temperature is 200 ° C, and then reacts with glycidyl acrylate or glycidyl methacrylate to prepare vinyl polyester resin, the cost of raw materials is high, and consumption High energy, not conducive to large-scale industrial production. It is reported in the literature that the preparation of UV-curable polyester resin needs to be esterified at a relatively high temperature (above 180°C), and the process of introducing vinyl or acrylic monomer is complicated and the cost is high.

Chinese invention patent application 2016111382348 (CN106748765A, 2017.5.31) discloses a UV curable polyester and its preparation method and application. Its preparation method is: 1) In terms of mole fraction, mix 1 part of triglycidyl ether and 3-4 parts of acrylic acid monomer in a reaction kettle, and add quaternary ammonium salt catalyst, polymerization inhibitor organic solvent in 105- React at 125°C until the acid value is lower than 10mgKOH/g; 2) Add acid anhydride, polymerization inhibitor and p-toluenesulfonic acid to the matrix prepared in step 1), react at 105-130°C for 2-4h, and then add moles of acid anhydride 0.9-1.2 times the number of epoxy compounds, and add a quaternary ammonium salt catalyst and an organic solvent to react until the acid value is less than 10mgKOH/g, remove the solvent by distillation under reduced pressure, cool down and discharge the material; the solid content of the resin reaches more than 100%, The viscosity is 3000-30000mPa·s. The UV curable coating prepared by the polyester has excellent film performance and low cost. However, the vinyl content of the polyester acrylic resin prepared by this technology is small, because a part of triglycidyl ether reacts with acrylic acid, and at most 3 vinyl groups can be introduced on the resin molecular chain, that is, the vinyl functionality of the product resin is 3, The crosslinking density of the coating film in the later stage of UV curing is low, which reduces the chemical resistance of the coating film. The starting triglycidyl ethers are mostly expensive, increasing the cost of UV-curable polyester acrylic resins.

Contents of the invention

The primary purpose of the present invention is to provide a relatively low cost, high cross-linking density, good chemical resistance, and energy-saving UV-curable unsaturated polyester resin with high vinyl functionality and a preparation method thereof; A UV curable polyester with a solid content of more than 85 wt % and a viscosity of 2000-6000 mPa·s (25° C.) is obtained.

Another object of the present invention is to provide the application of the UV curable resin prepared by the above method in coatings. The coating film prepared by adopting the UV curable resin of the invention has excellent performance, and the coating film hardness can reach 2H.

The object of the present invention is achieved through the following technical solutions:

The invention discloses a method for preparing a UV-curable unsaturated polyester resin with high vinyl functionality. The mass percentage consists of: acid anhydride: 33-42%, vinyl glycidyl ether: 11-24%, epoxy compound: 18-34%, Inhibitor 0.1-0.5%, organic solvent 10-20%. The preparation steps are as follows: under the protection of nitrogen, add acid anhydride, epoxy compound, catalyst and solvent into a three-necked flask equipped with a stirrer and a thermometer, stir and heat to 90-120°C and keep it warm for 1-3h; Add vinyl glycidyl ether dissolved in a polymerization inhibitor dropwise within 2 hours, conduct ring-opening copolymerization reaction at 90-120°C for 4-6 hours, measure the acid value of the reaction system to below 15mg KOH/g, and remove unreacted by vacuum distillation monomer and solvent to obtain light yellow transparent unsaturated polyester.

The acid anhydrides include one or more of phthalic anhydride, trimellitic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride and pyromellitic dianhydride.

The epoxy compound includes one or both of epichlorohydrin, n-butyl glycidyl ether, octyl glycidyl ether, benzyl glycidyl ether, glycidyl tert-carbonate and C12 _～14 glycidyl ether. more than one species.

The vinyl glycidyl ether includes one or both of glycidyl methacrylate, allyl glycidyl ether, 4-vinylbenzyl glycidyl ether and 4-hydroxybutyl acrylate glycidyl ether above.

The solvent includes one or more of ethyl acetate, butyl acetate, butanone and cyclohexanone.

The catalyst includes one or more of tetraethylammonium bromide, tetrabutylammonium bromide, tetraoctylammonium bromide and zinc acetate. The dosage of the catalyst is 1%-5% of the mass of the acid anhydride.

The polymerization inhibitor includes one or more of hydroquinone, p-hydroxyanisole and tert-butylcatechol.

A UV-curable unsaturated polyester resin with high vinyl functionality, prepared by the above preparation method, has a viscosity of 2000-6000mPa·s at 25°C.

The application of the UV-curable unsaturated polyester resin with high vinyl functionality in coatings includes adding a reactive diluent and a photoinitiator to the polyester, and the mass percentage is composed of: polyester resin 65% to 75%, reactive diluent 20-35%, photoinitiator 2-5%, other additives 0.1-0.5%, film-forming by UV curing. The active diluent includes trimethylolpropane triacrylate, tripropylene glycol diacrylate, hexanediol diacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate and acryloyl morpholine, etc. or two or more;

The photoinitiators include 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (Lucirin TPO), 2-hydroxy-2-methyl-1-phenyl-1-propanone (Darocur 1173) One or more of 1-hydroxycyclohexyl phenyl ketone, etc.;

The other additives include one or more of leveling agent, substrate wetting agent and defoamer.

The leveling agent includes one or more of German BYK 358N, BYK 306 and BYK 371;

The defoamer includes one or more of BYK 024, BYK 028 and BYK 141 of BYK, Germany;

The substrate wetting agent includes one or more of TEGO 2250, TEGO 270 and TEGO 245 from Evonik Degussa. Its UV curable coating has a pencil hardness of 2H and has excellent water resistance and alcohol resistance.

Technical principle of the present invention is as follows:

The present invention prepares the unsaturated aliphatic polyester through the ring-opening polymerization of the epoxy group of the acid anhydride and vinyl glycidyl ether; in the polymerization reaction system, the acid anhydride first coordinates with the catalyst, activates, and opens the ring to generate an ester group anion, The anion attacks the epoxy group coordinated and activated by the catalyst, causing the epoxy group to open and insert into the polymer main chain, and the acid anhydride and vinyl glycidyl ether are alternately inserted into the polymer chain to form a polyester containing a large number of vinyl groups. The polyester molecular chain contains a large amount of vinyl glycidyl ether, the vinyl functionality is very high, and can be cured by UV; in order to regulate the vinyl functionality of the unsaturated polyester, an epoxy compound without vinyl is used to participate Polymerization reaction reduces the amount of vinyl glycidyl ether added, and also reduces the viscosity and cost of the resin.

Compared with prior art, the present invention has following advantage:

1. The present invention prepares the unsaturated polyester of high vinyl functionality by the ring-opening polymerization of acid anhydride and vinyl glycidyl ether, which is used for UV-curable coatings; the method uses wide sources of raw materials, low price, and few reaction steps. The formula is simple, the difficulty of industrial operation is low, and compared with the existing technology, it can save a lot of cost, and is very suitable for industrial mass production;

2. Compared with the traditional reaction of acid and alcohol to produce polyester, this reaction does not produce by-product water, does not need benzene substances as water-carrying agents and solvents, and the reaction temperature does not exceed 120 ° C, the process is simpler, energy saving and consumption reduction. Safety and environmental protection;

3. The polyester resin prepared by the present invention has high coating film hardness and excellent adhesion after UV curing to form a film. In addition, the coating film has high gloss and good medium resistance.

Description of drawings

Fig. 1 is the infrared spectrogram of the product UV curable polyester in Example 1.

FIG. 2 is a structural diagram of the UV-curable polyester prepared in Example 1. FIG. Wherein, structural formula 1 is the product polymer structural formula of the reaction between phthalic anhydride and methacrylic acid glycidyl ether; structural formula 2 is the product structural formula of adding n-butyl glycidyl ether in the reaction of Example 1.

Detailed ways

In order to better understand the present invention, the present invention will be further described below in conjunction with the accompanying drawings and examples, but the embodiments of the present invention are not limited thereto.

The BASF Laromer LR 9004 compared in the embodiment is produced by BASF, Germany, and is mainly used in the elastic polyester acrylate of paper, PVC, wood and wood products radiation curing varnish and printing ink production purposes, with good stability and low temperature Flexibility, belongs to a class of polyester acrylic resin with a large market share.

In the following examples, the performance of UV-curable polyester resin and light-curable coating is detected according to the following methods: use NDJ-1 type rotational viscometer to measure resin viscosity according to GB/T 21059-2007; measure resin acid value according to GB/T 6743-2008 ; Measure the hardness of the coating film according to GB/T 6739-2006; measure the adhesion of the coating film according to GB/T 9286-1998; /T 5209-1985 uses room temperature immersion method to measure the water resistance of the coating film; according to GB/T 4893.1-2005, the alcohol resistance of the coating film is measured.

Example 1

1) A UV-curable unsaturated polyester resin with high vinyl functionality, the mass percentage composition of the raw material formula is as shown in Table 1 (catalyst is not included):

Table 1

2) The preparation technology of UV-curable unsaturated polyester resin with high vinyl functionality comprises the following steps:

Molecular structural formula 1 in Fig. 2 is the product polymer structural formula of phthalic anhydride and methacrylic acid glycidyl ether reaction, and wherein n is the number of repeating chain link, generally greater than 6; By adjusting phthalic anhydride and methacrylic acid glycidyl ether The ratio of the amount of the substance to control the molecular weight of the product is generally above 2000, that is, the n value is 6-10. Structural formula 2 in Figure 2 is the product structural formula of adding n-butyl glycidyl ether in the above reaction, and its main function is to regulate the functionality of the vinyl group in the unsaturated polyester, that is, the vinyl content, thereby regulating the crosslinking density of the coating film , and then control the hardness of the coating film, chemical resistance and cost.

Under nitrogen protection, add phthalic anhydride, n-butyl glycidyl ether, ethyl acetate and tetraethylammonium bromide (1.0% of the mass fraction of anhydride) to a flask equipped with a stirrer and a thermometer according to a given mass. ) mix evenly, raise the temperature to 90°C and keep it warm for 1h, then add glycidyl methacrylate dissolved in hydroquinone drop by drop, finish dripping in 1.5h, perform ring-opening copolymerization reaction at 100°C for 4h until the acid value drops to 15mgKOH/ g, lower the temperature and discharge to obtain UV curable unsaturated aliphatic polyester.

3) Physical and chemical properties of the UV-curable polyester resin obtained by the above preparation method: Appearance: pale yellow and transparent; solid content: 88.41%; acid value: 8.5mgKOH/g, viscosity (25°C): 4075mPa·s.

4) Preparation and properties of UV curable coatings

In parts by mass, the composition of the UV curable coating is as follows in Table 2:

Table 2

Add the above-mentioned formula substances into the container, disperse at a low speed of 600r/min for 10-15min, and filter through a 300-mesh filter cloth to obtain a UV-curable coating. The coating was cured under a UV curing machine with an energy of 600mJ/cm ² on a wooden board and a glass board respectively.

The performance of the coating film was measured and compared with the performance of BASF Laromer LR 9004, as shown in Table 3 below:

table 3

Table 3 shows that the UV curable polyester resin coating film prepared in this example has high gloss, high hardness and excellent water resistance.

Figure 1 is the infrared spectrogram of the prepared UV curable polyester resin, in which there is no carbonyl vibration absorption peak of phthalic anhydride at 1760cm ^-1 and 1850cm- ¹ , which proves that the acid anhydride reacts during the ring-opening copolymerization; There are no characteristic absorption peaks of epoxy groups at around 905 and 913 cm ^-1 , which proves that epoxy compounds and acid anhydrides undergo a ring-opening reaction to form the structure shown in Figure 2 Structural Formula 2; a strong and sharp ester appears at 1726 cm ^-1 The carbonyl peak and the characteristic absorption peak of -C=C- appear at 1640cm ^-1 , which proves the generation of UV-curable unsaturated polyester. Molecular structural formula 1 in Fig. 2 is the product polymer structural formula of phthalic anhydride and methacrylic acid glycidyl ether reaction, and wherein n is the number of repeating chain link, generally greater than 6; By adjusting phthalic anhydride and methacrylic acid glycidyl ether The ratio of the amount of the substance to control the molecular weight of the product is generally above 2000, that is, the n value is 6-10. Structural formula 2 in Figure 2 is the product structural formula of adding n-butyl glycidyl ether in the above reaction, and its main function is to regulate the functionality of the vinyl group in the unsaturated polyester, that is, the vinyl content, thereby regulating the crosslinking density of the coating film , and then control the hardness of the coating film, chemical resistance and cost.

Compared with the Chinese invention patent application 2016111382348 (CN106748765A, 2017.5.31), the vinyl functionality in this example increases from 3 to more than 6, and the preparation process changes from a two-step process to a one-step process without using the price Expensive triglycidyl ether is used as the starting material; by changing the type and proportion of epoxy monomers, the vinyl functionality, viscosity and performance of unsaturated polyester can be effectively regulated, and high solid content, low viscosity UV curing can be prepared polyester. Therefore, this embodiment has UV curable unsaturated resin with high vinyl functionality, high hardness of UV curable coating film, good chemical resistance, simple process and low cost. For the reaction of polyester with traditional alcohol and acid (CN105061738A and CN105504245A), the present invention does not need to react at 180-240°C, the reaction temperature is relatively low, no more than 120°C, no by-product water is produced, and benzene is not required as a belt Water agent, more green and environmental protection, simple process, energy saving and consumption saving.

Example 2

1) A UV-curable unsaturated polyester resin with high vinyl functionality, the mass percentage composition of the raw material formula is as shown in Table 4 (catalyst is not included):

Table 4

2) The preparation technology of UV-curable unsaturated polyester resin with high vinyl functionality, comprising the following steps:

Under the protection of nitrogen, add phthalic anhydride, octyl glycidyl ether, butyl acetate and tetrabutylammonium bromide (1.2% of the mass fraction of anhydride) in a flask equipped with a stirrer and a thermometer according to a given mass Mix evenly, raise the temperature to 100°C and keep it warm for 2.5h, then add glycidyl methacrylate dissolved in hydroquinone dropwise, drop it in 1h, and perform ring-opening copolymerization reaction at 110°C for 4.5h until the acid value drops to 15mgKOH/ g, lower the temperature and discharge to obtain UV curable unsaturated aliphatic polyester.

3) Physical and chemical properties of the UV-curable polyester resin obtained by the above preparation method: appearance: light yellow and transparent; solid content: 89.25%; acid value: 9.6mgKOH/g, viscosity (25°C): 3560mPa·s.

4) Preparation and properties of UV curable coatings

In parts by mass, the composition of the UV curable coating is as follows in Table 5:

table 5

Add the above-mentioned formula substances into the container, disperse at a low speed of 600r/min for 10-15min, and filter through a 300-mesh filter cloth to obtain a UV-curable coating. The coating was cured under a UV curing machine with an energy of 600mJ/cm ² on a wooden board and a glass board respectively.

The performance of the coating film was measured and compared with the performance of BASF Laromer LR 9004, as shown in Table 6 below:

Table 6

Example 3

1) A UV-curable unsaturated polyester resin with high vinyl functionality, the mass percentage composition of the raw material formula is shown in Table 7 (catalyst is not included):

Table 7

2) The preparation technology of UV-curable unsaturated polyester resin with high vinyl functionality comprises the following steps:

Under the protection of nitrogen, add hexahydrophthalic anhydride, benzyl glycidyl ether, butyl acetate and tetrabutylammonium bromide (1.5% of the mass fraction of acid anhydride) according to a given mass into a flask equipped with a stirrer and a thermometer, and mix well , heat up to 110°C for 3 hours, then add allyl glycidyl ether dissolved in tert-butyl catechol dropwise, drop after 1 hour, and perform ring-opening copolymerization reaction at 110°C for 6 hours until the acid value drops to 15mgKOH/g, Cool down and discharge to obtain UV curable unsaturated aliphatic polyester.

3) Physical and chemical properties of the UV-curable polyester resin obtained by the above preparation method: appearance: light yellow and transparent; solid content: 87.92%; acid value: 9.5mgKOH/g, viscosity (25°C): 4580mPa·s.

4) Preparation and properties of UV curable coatings

In terms of parts by mass, the composition of the UV curable coating is as follows in Table 8:

Table 8

Add the above-mentioned formula substances into the container, disperse at a low speed of 600r/min for 10-15min, and filter through a 300-mesh filter cloth to obtain a UV-curable coating. The coating was cured under a UV curing machine with an energy of 600mJ/cm ² on a wooden board and a glass board respectively.

The performance of the coating film was measured and compared with the performance of BASF Laromer LR 9004, as shown in Table 9 below:

Table 9

Example 4

1) A UV-curable unsaturated polyester resin with high vinyl functionality, the mass percentage composition of the raw material formula is shown in Table 10 (catalyst is not included):

Table 10

2) the preparation technology of this UV curable polyester resin, comprises the following steps:

Under nitrogen protection, add succinic anhydride, n-butyl glycidyl ether, methyl ethyl ketone and zinc acetate (1.5% of the mass fraction of acid anhydride) by given mass in the flask equipped with a stirrer and a thermometer, mix well, and heat up to 90 Insulate at ℃ for 3 hours, then add 4-vinylbenzyl glycidyl ether dissolved in p-hydroxyanisole drop by drop, finish dropping in 2 hours, perform ring-opening copolymerization reaction at 100℃ for 4 hours until the acid value drops to 15mgKOH/g, then cool down Discharging to obtain UV curable unsaturated aliphatic polyester.

(3) The physical and chemical properties of the UV-curable polyester resin obtained by the above preparation method: appearance: light yellow and transparent; solid content: 86.98%; acid value: 11.3mgKOH/g, viscosity (25°C): 2750mPa·s.

(4) Preparation and properties of UV curable coatings

In parts by mass, the composition of the UV curable coating is as follows in Table 11:

Table 11

Add the above-mentioned formula substances into the container, disperse at a low speed of 600r/min for 10-15min, and filter through a 300-mesh filter cloth to obtain a UV-curable coating. The coating was cured under a UV curing machine with an energy of 600mJ/cm ² on a wooden board and a glass board respectively.

The performance of the coating film was measured and compared with the performance of BASF Laromer LR 9004, as shown in Table 12 below:

Table 12

Example 5

1) A UV-curable unsaturated polyester resin with high vinyl functionality, the mass percentage composition of the raw material formula is shown in Table 13 (catalyst is not included):

Table 13

2) The preparation technology of UV-curable unsaturated polyester resin with high vinyl functionality, comprising the following steps:

Under nitrogen protection, add phthalic anhydride, n-butyl glycidyl ether, glycidyl tert-carbonate, ethyl acetate and tetrabutylammonium bromide ( 3.0% of the mass fraction of acid anhydride) and mix evenly, raise the temperature to 110°C and keep it warm for 2h, then add 4-hydroxybutyl acrylate glycidyl ether dissolved in p-hydroxyanisole dropwise, drop it for 1h, and open the ring at 110°C Copolymerize for 5 hours until the acid value drops to 15 mgKOH/g, then cool down and discharge to obtain UV-curable unsaturated aliphatic polyester.

3) Physical and chemical properties of the UV-curable polyester resin obtained by the above preparation method: appearance: light yellow and transparent; solid content: 88.86%; acid value: 8.4mgKOH/g, viscosity (25°C): 3925mPa·s.

4) Preparation and properties of UV curable coatings

In parts by mass, the composition of the UV curable coating is as follows in Table 14:

Table 14

Add the above-mentioned formula substances into the container, disperse at a low speed of 600r/min for 10-15min, and filter through a 300-mesh filter cloth to obtain a UV-curable coating. The coating was cured under a UV curing machine with an energy of 600mJ/cm ² on a wooden board and a glass board respectively.

The performance of the coating film was measured and compared with the performance of BASF Laromer LR 9004, as shown in Table 15 below:

Table 15

Example 6

1) A UV-curable unsaturated polyester resin with high vinyl functionality, the mass percentage composition of the raw material formula is shown in Table 16 (catalyst is not included):

Table 16

2) The preparation technology of UV-curable unsaturated polyester resin with high vinyl functionality, comprising the following steps:

Under the protection of nitrogen, add succinic anhydride, benzyl glycidyl ether, epichlorohydrin, ethyl acetate and zinc acetate (2.5% of the mass fraction of acid anhydride) according to a given mass in a flask equipped with a stirrer and a thermometer. Evenly, heat up to 90°C and keep it warm for 2 hours, then add glycidyl methacrylate dissolved in hydroquinone drop by drop, drop after 1 hour, and perform ring-opening copolymerization reaction at 90°C for 6 hours until the acid value drops to 15mgKOH/g, Cool down and discharge to obtain UV curable unsaturated aliphatic polyester.

(3) The physical and chemical properties of the UV-curable polyester resin obtained by the above preparation method: appearance: light yellow and transparent; solid content: 90.32%; acid value: 9.7mgKOH/g, viscosity (25°C): 2855mPa·s.

(4) Preparation and properties of UV curable coatings

In parts by mass, the composition of the UV curable coating is as follows in Table 17:

Table 17

Add the above-mentioned formula substances into the container, disperse at a low speed of 600r/min for 10-15min, and filter through a 300-mesh filter cloth to obtain a UV-curable coating. The coating was cured under a UV curing machine with an energy of 600mJ/cm ² on a wooden board and a glass board respectively.

The performance of the coating film was measured and compared with the performance of BASF Laromer LR 9004, as shown in Table 18 below:

Table 18

Example 7

1) A UV-curable unsaturated polyester resin with high vinyl functionality, the mass percentage composition of the raw material formula is shown in Table 19 (catalyst is not included):

Table 19

2) The preparation technology of UV-curable unsaturated polyester resin with high vinyl functionality, comprising the following steps:

Under nitrogen protection, add methyl hexahydrophthalic anhydride, benzyl glycidyl ether, _C12-14 glycidyl ether, butanone and tetrabutylammonium bromide ( 1.2% of the mass fraction of acid anhydride) and mix evenly, raise the temperature to 100°C and keep it warm for 2.5h, then add allyl glycidyl ether dissolved in hydroquinone dropwise, drop it in 1h, and perform the ring-opening copolymerization reaction at 100°C for 6h to When the acid value drops to 15 mgKOH/g, the temperature is lowered and the material is discharged to obtain a UV-curable unsaturated aliphatic polyester.

3) Physical and chemical properties of the UV-curable polyester resin obtained by the above preparation method: appearance: light yellow and transparent; solid content: 90.02%; acid value: 10.5mgKOH/g, viscosity (25°C): 3365mPa·s.

4) Preparation and properties of UV curable coatings

In parts by mass, the composition of the UV curable coating is as follows in Table 20:

Table 20

Add the above-mentioned formula substances into the container, disperse at a low speed of 600r/min for 10-15min, and filter through a 300-mesh filter cloth to obtain a UV-curable coating. The coating was cured under a UV curing machine with an energy of 600mJ/cm ² on a wooden board and a glass board respectively.

The performance of the coating film was measured and compared with the performance of BASF Laromer LR 9004, as shown in Table 21 below:

Table 21

Example 8

1) A UV-curable unsaturated polyester resin with high vinyl functionality, the mass percentage composition of the raw material formula is shown in Table 22 (catalyst is not included):

Table 22

2) The preparation technology of UV-curable unsaturated polyester resin with high vinyl functionality comprises the following steps:

Under nitrogen protection, add trimellitic anhydride, n-butyl glycidyl ether, C _12-14 glycidyl ether, cyclohexanone and tetraoctyl ammonium bromide according to the given mass to the flask equipped with a stirrer and a thermometer (the amount of anhydride 4.0% of the fraction) mix evenly, raise the temperature to 120°C and keep it warm for 3h, then add glycidyl methacrylate dissolved in tert-butyl catechol drop by drop, finish dropping in 1h, and perform ring-opening copolymerization reaction at 120°C for 6h to reach the acid value When the temperature drops to 15mgKOH/g, the temperature is lowered and the material is discharged to obtain a UV-curable unsaturated aliphatic polyester.

(3) Physical and chemical properties of the UV-curable polyester resin obtained by the above preparation method: appearance: light yellow and transparent; solid content: 90.25%; acid value: 7.8mgKOH/g, viscosity (25°C): 5275mPa·s.

(4) Preparation and properties of UV curable coatings

In terms of parts by mass, the composition of the UV curable coating is as follows in Table 23:

Table 23

Add the above-mentioned formula substances into the container, disperse at a low speed of 600r/min for 10-15min, and filter through a 300-mesh filter cloth to obtain a UV-curable coating. The coating was cured under a UV curing machine with an energy of 600mJ/cm ² on a wooden board and a glass board respectively.

The performance of the coating film was measured and compared with the performance of BASF Laromer LR 9004, as shown in Table 24 below:

Table 24

The UV curable polyester prepared by the invention has the characteristics of simple preparation process, low VOC emission, energy saving and environmental protection, and the prepared coating film has the advantages of high gloss, good water resistance, high hardness and the like.

It should be noted that the present invention is not restricted by the above-mentioned embodiments, and any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent alternatives, including Within the protection scope of the present invention.

Claims (9)

1. The preparation method of UV-curable unsaturated polyester resin with high vinyl functionality is characterized in that, in terms of mass percentage, its raw materials consist of: 33% to 42% of acid anhydride, 11% to 24% of vinyl glycidyl ether, Epoxy compound 18-34%, polymerization inhibitor 0.1-0.5%, organic solvent 10-20%; during preparation, under the protection of nitrogen, the acid anhydride, epoxy compound, catalyst and solvent were stirred and heated to 90-120°C and Insulate for 1-3h; then add vinyl glycidyl ether dissolved in polymerization inhibitor dropwise within 1-2h, ring-opening copolymerization reaction at 90-120°C for 4-6h, measure the acid value of the reaction system to 15mg KOH/g Below, unreacted monomer and solvent are removed by distillation under reduced pressure to obtain UV curable unsaturated polyester resin; The acid anhydride is one or more of phthalic anhydride, succinic anhydride, trimellitic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride and pyromellitic dianhydride; The epoxy compound is one or both of epichlorohydrin, n-butyl glycidyl ether, octyl glycidyl ether, benzyl glycidyl ether, glycidyl tert-carbonate and _C12-14 glycidyl ether. more than one species; The vinyl glycidyl ether is one or both of glycidyl methacrylate, allyl glycidyl ether, 4-vinylbenzyl glycidyl ether and 4-hydroxybutyl acrylate glycidyl ether above; The catalyst is one or more of tetrabutylammonium bromide, tetraethylammonium bromide, tetraoctylammonium bromide and zinc acetate. 2. the preparation method of the UV-curable unsaturated polyester resin of high vinyl functionality according to claim 1 is characterized in that: described solvent is ethyl acetate, butyl acetate, butanone and cyclohexanone one or more of them. 3. the preparation method of the UV-curable unsaturated polyester resin of high vinyl functionality according to claim 1, is characterized in that: described polymerization inhibitor is hydroquinone, p-hydroxyanisole and tert-hydroxyanisole One or two or more of butyl catechols. 4. The method for preparing UV-curable unsaturated polyester resin with high vinyl functionality according to claim 1, characterized in that: the amount of the catalyst is 1% to 5% of the mass of the acid anhydride. 5. A UV-curable unsaturated polyester resin with high vinyl functionality, characterized in that: it is prepared by the preparation method described in any one of claims 1-5, and has a viscosity of 2000 to 6000 mPa at 25°C. s. 6. The application of the UV-curable unsaturated polyester resin of high vinyl functionality described in any one of claims 1-5 in coatings is characterized in that: reactive diluent is added in the UV-curable unsaturated polyester resin agent, photoinitiator and other additives; in terms of mass percentage, the raw material composition of the coating is: 65-75% of UV-curable unsaturated polyester resin, 20-30% of reactive diluent, 2-5% of photoinitiator, 0.1-0.5% of other additives, the resulting UV cured coating has a pencil hardness of 2H, good water resistance and alcohol resistance. 7. the application of the UV-curable unsaturated polyester resin of high vinyl functionality according to claim 6 in coatings is characterized in that: the photoinitiator is 2,4,6-trimethylbenzene One or more of formyl-diphenylphosphine oxide, 2-hydroxy-2-methyl-1-phenyl-1-propanone and 1-hydroxycyclohexyl phenyl ketone. 8. The application of the UV-curable unsaturated polyester resin of high vinyl functionality according to claim 6 in coatings is characterized in that: the reactive diluent is trimethylolpropane triacrylate, three One or more of propylene glycol diacrylate, hexanediol diacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate and acryloyl morpholine. 9. the application of the UV-curable unsaturated polyester resin of high vinyl functionality according to claim 6 in coatings, is characterized in that: other described auxiliary agents are leveling agent, substrate wetting agent and One or more than two kinds of defoamers; The leveling agent is one or more of German BYK 358N, BYK 306 and BYK 371; The defoamer is one or more of BYK 024, BYK 028 and BYK 141 of BYK, Germany; The substrate wetting agent is one or more of TEGO 2250, TEGO 270 and TEGO 245 produced by Evonik Degussa.