Hyperbranched polyurethane acrylate UV light-cured resin and preparation method thereof

Abstract

The invention discloses hyperbranched polyurethane acrylate UV light-cured resin and a preparation method thereof, and belongs to the technical field of resin material preparation, the structure of the resin is shown as a structural formula I, and the structure of R is one or more than two of structural formulas II, III and IV. The preparation method comprises the following steps: S1, preparing an end-capping reagent; s2, reacting an end-capping reagent with the hyperbranched polyester polyol to generate hyperbranched polyurethane acrylate UV light-cured resin; wherein the end-capping reagent comprises IH as shown in a structural formula V or IF as shown in a structural formula VI or isocyanate ethyl acrylate. The hyperbranched core is introduced, and polyurethane and acrylate resin are hybridized, so that the curing speed and the coating hardness of a cured film are improved, the toughness of a rigid cured film is improved, and the high wear and scratch resistance of a high-hardness material is realized. # imgabs0 #

Description

Technical Field

[0001] The invention belongs to the technical field of resin material preparation, and particularly relates to a hyperbranched polyurethane acrylate UV light-curing resin and a preparation method thereof. Background Art

[0002] With the rapid development of polymer materials science, polyurethane acrylate (PUA), as an important polymer material, has been widely used in coatings, inks, adhesives, etc. due to its excellent physical and mechanical properties, good chemical stability and adjustable processing properties. In particular, hyperbranched polyurethane acrylate has great application potential in the field of UV light curing due to its unique three-dimensional network structure and high-density functional groups.

[0003] In recent years, polyurethane acrylate end-capping agents IH and IF prepared by reacting acrylate raw materials such as hydroxyethyl acrylate (HEA) and 2-(methacryloyloxy)ethyl caprolactone (IF1D) with isophorone diisocyanate (IPDI) have become a research hotspot in the field of UV light curing. These end-capping agents not only increase the cross-linking density of the resin, but also enhance the hardness and scratch resistance of the cured film. Furthermore, IH and IF are combined with isocyanate ethyl acrylate (AOI) and reacted with hyperbranched polyester polyols to synthesize hyperbranched polyurethane acrylates of different structures, providing a new idea for the preparation of UV light curing resins.

[0004] With the increasingly stringent environmental protection requirements and the need for efficient production, UV light curing technology is increasingly widely used in coatings, inks, adhesives and other fields due to its fast curing, low energy consumption and low pollution. As an important component of UV light curing resin, hyperbranched polyurethane acrylate has excellent performance and broad application prospects, which has led to a continuous increase in related research. Especially in the fields with high hardness and high scratch resistance requirements, such as automobiles, electronics, aerospace and other industries, the application prospects of hyperbranched polyurethane acrylate are particularly broad.

[0005] Although the application of hyperbranched polyurethane acrylates in the field of UV light curing has made significant progress, it still faces some technical bottlenecks. First, how to further improve the viscosity stability and cross-linking density of the resin to meet more complex and harsh application environments is an urgent problem to be solved. Secondly, how to balance the hardness and toughness of the resin so that it can meet the hardness requirements while still maintaining good flexibility and impact resistance is also a difficulty in current research. In addition, how to reduce production costs and improve production efficiency is also the key to promoting the practical application of hyperbranched polyurethane acrylates. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a hyperbranched polyurethane acrylate UV light-curing resin and a preparation method thereof, and the specific scheme is as follows:

[0007] First, the present invention provides a hyperbranched polyurethane acrylate UV light-curing resin, the structure of which is shown in structural formula I:

[0008]

[0009]

[0010] Wherein, R' represents polydipentaerythritol, and the structure of R is one or more of the following structural formulas II, III, and IV:

[0011]

[0012] Second, the present invention provides a method for preparing the above-mentioned hyperbranched polyurethane acrylate UV light-curable resin, comprising the following steps:

[0013] S1, preparing a capping agent;

[0014] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0015] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or ethyl isocyanate acrylate:

[0016]

[0017] Preferably, the preparation of the end-capping agent in S1 specifically comprises: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF, and the reaction formula is as follows:

[0018]

[0019] Preferably, the reaction is carried out under stirring conditions.

[0020] Preferably, the molar ratio of IPDI in S1 to the end-capping agent HEA or the end-capping agent FM1D is 1:1.

[0021] Preferably, the catalyst in S1 is T-12 catalyst, and the dosage is 200-500 ppm based on IPDI.

[0022] Preferably, in the reaction of S1, the reaction temperature is 30-75°C and the reaction time is 3-4h.

[0023] Preferably, the catalyst in S1 is a composite catalyst, which includes T-12 catalyst and TEA, and the molar ratio of the two is 1:(1-4), and the amount of the catalyst is 200-500ppm based on the amount of IPDI.

[0024] Preferably, in the reaction of S1, the reaction temperature is 60-75°C and the reaction time is 1-2h.

[0025] Preferably, the reaction in S2 specifically comprises: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and reacting by heating to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0026] Preferably, the amount of the hyperbranched polyester polyol in S2 is equivalent to the added IH or IF.

[0027] Preferably, in the reaction of S2, the reaction temperature is 30-100°C and the reaction time is 24-48h.

[0028] Preferably, the reaction in S2 is stopped after the disappearance of the isocyanate group NCO is detected.

[0029] Preferably, the solvent in S2 includes one or more of MEK, EOEOEA and NVP.

[0030] Preferably, in the reaction of S2, 1,4-butanediol (BDO) is further added in an amount of 8-15% of the molar amount of the hyperbranched polyester polyol.

[0031] Preferably, in the reaction of S2, the reaction temperature is 80-100° C., the reaction time is 24-48 h, and the reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0032] Beneficial Effects

[0033] The invention not only improves the curing speed and coating hardness of the cured film, but also improves the toughness of the rigid cured film by introducing a hyperbranched core and hybridizing polyurethane with an acrylate resin, thereby achieving high wear and scratch resistance of high-hardness materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The photos are of PUA samples synthesized in Examples 1-7. The sample annotations indicate the hyperbranched polyol model used in the preparation process;

[0035] Figure 2 The surface appearance photos of the UV-cured films prepared from the PUA samples synthesized in Examples 1-7, and the sample annotations indicate the model of the hyperbranched polyol used in the preparation process;

[0036] Figure 3Schematic diagram of thin layer chromatography analysis of IH / IF prepared in the examples;

[0037] Figure 4 This is the GPC curve of IH / IF prepared in the example, after IH and IPDI were capped with di-n-butylamine;

[0038] Figure 5 FT-IR spectra of the end-capping agents IH and IF and the reaction raw materials;

[0039] Figure 6 is the 1H-NMR spectrum of the capping agent IH;

[0040] Figure 7 MS-ESI spectrum of the end-capping agent IH obtained in Example;

[0041] Figure 8 FT-IR spectrum of the hyperbranched polyurethane acrylate UV light-curing resin obtained in Example;

[0042] Fig. 9 : is the GPC curve of the hyperbranched polyurethane acrylate UV light-curing resin obtained in Example;

[0043] Fig.10 The FT-IR spectrum of the UV-cured resin cured film with the formula shown in Table 5. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0045] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0046] The experimental methods in the following examples are conventional methods unless otherwise specified, and the experimental materials used in the following examples are purchased from commercial channels unless otherwise specified.

[0047] Example 1 Preparation of hyperbranched polyurethane acrylate UV light-curing resin:

[0048] S1, preparing a capping agent;

[0049] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0050] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0051] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0052] The reaction is carried out under stirring conditions.

[0053] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0054] The catalyst described in S1 is T-12 catalyst, and the dosage is 200ppm based on the dosage of IPDI.

[0055] The reaction described in S1, the reaction temperature is 60°C, and the reaction time is 1h.

[0056] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0057] The hyperbranched polyester polyol described in S2 is H500, the dosage is 0.01 mol, and the added end-capping agent is IH, the added dosage is 0.19 mol.

[0058] The reaction described in S2 is carried out at a temperature of 50° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0059] The solvent in S2 is MEK, and the added amount is 25%wt of the entire reaction system.

[0060] Example 2 Preparation of hyperbranched polyurethane acrylate UV light-curing resin:

[0061] S1, preparing a capping agent;

[0062] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0063] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0064] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0065] The reaction is carried out under stirring conditions.

[0066] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0067] The catalyst described in S1 is T-12 catalyst, and the dosage is 200ppm based on the dosage of IPDI.

[0068] The reaction described in S1, the reaction temperature is 60°C, and the reaction time is 2h.

[0069] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0070] The hyperbranched polyester polyol described in S2 is F500, the dosage is 0.01 mol, and the end-capping agent added is IF, the addition amount is 0.19 mol.

[0071] The reaction described in S2 is carried out at a temperature of 50° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0072] The solvent in S2 is MEK, and the added amount is 25%wt of the entire reaction system.

[0073] Example 3 Preparation of hyperbranched polyurethane acrylate UV light-curing resin:

[0074] S1, preparing a capping agent;

[0075] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0076] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0077] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0078] The reaction is carried out under stirring conditions.

[0079] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0080] The catalyst described in S1 is T-12 catalyst, and the dosage is 200ppm based on the dosage of IPDI.

[0081] The reaction described in S1, the reaction temperature is 30°C, and the reaction time is 3h.

[0082] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0083] The hyperbranched polyester polyol described in S2 is HE500, the dosage is 0.01 mol, and the added end-capping agent is IH, the added dosage is 0.19 mol.

[0084] The reaction described in S2 is carried out at a temperature of 50° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0085] The solvent in S2 is EOEOEA, and the added amount is 25%wt of the entire reaction system.

[0086] Example 4 Preparation of hyperbranched polyurethane acrylate UV light-curing resin:

[0087] S1, preparing a capping agent;

[0088] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0089] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0090] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0091] The reaction is carried out under stirring conditions.

[0092] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0093] The catalyst described in S1 is T-12 catalyst, and the dosage is 0.

[0094] The reaction described in S1, the reaction temperature is 30°C, and the reaction time is 3h.

[0095] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0096] The hyperbranched polyester polyol described in S2 is HN500, the dosage is 0.01 mol, and the end-capping agent added is IH, the addition amount is 0.19 mol.

[0097] The reaction described in S2 is carried out at a temperature of 30° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0098] The solvent in S2 is NVP, and the amount added is 25%wt of the entire reaction system.

[0099] Example 5 Preparation of hyperbranched polyurethane acrylate UV light-curing resin:

[0100] S1, preparing a capping agent;

[0101] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0102] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0103] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0104] The reaction is carried out under stirring conditions.

[0105] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0106] The catalyst described in S1 is T-12 catalyst, and the dosage is 200ppm based on the dosage of IPDI.

[0107] The reaction described in S1, the reaction temperature is 30°C, and the reaction time is 3h.

[0108] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0109] The hyperbranched polyester polyol described in S2 is FE500, the dosage is 0.01 mol, and the end-capping agent added is IF, the addition amount is 0.19 mol.

[0110] The reaction described in S2 is carried out at a temperature of 50° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0111] The solvent in S2 is EOEOEA, and the added amount is 25%wt of the entire reaction system.

[0112] Example 6 Preparation of hyperbranched polyurethane acrylate UV light-curing resin:

[0113] S1, preparing a capping agent;

[0114] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0115] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0116] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0117] The reaction is carried out under stirring conditions.

[0118] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0119] The catalyst described in S1 is T-12 catalyst, and the dosage is 0.

[0120] The reaction described in S1, the reaction temperature is 30°C, and the reaction time is 3h.

[0121] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0122] The hyperbranched polyester polyol described in S2 is FN500, the dosage is 0.01 mol, and the end-capping agent added is IF, the addition amount is 0.19 mol.

[0123] The reaction described in S2 is carried out at a temperature of 30° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0124] The solvent in S2 is NVP, and the amount added is 25%wt of the entire reaction system.

[0125] Example 7 Preparation of hyperbranched polyurethane acrylate UV light-curing resin:

[0126] S1, preparing a capping agent;

[0127] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0128] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0129] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0130] The reaction is carried out under stirring conditions.

[0131] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0132] The catalyst described in S1 is T-12 catalyst, and the dosage is 200ppm based on the dosage of IPDI.

[0133] The reaction described in S1, the reaction temperature is 30°C, and the reaction time is 3h.

[0134] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0135] The hyperbranched polyester polyol described in S2 is AE500, the dosage is 0.01 mol, and the end-capping agent added is AOI, the addition amount is 0.19 mol.

[0136] The reaction described in S2 is carried out at a temperature of 50° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0137] The solvent in S2 is EOEOEA, and the added amount is 25%wt of the entire reaction system.

[0138] Example 8 (Based on Example 5) Preparation of hyperbranched polyurethane acrylate UV light-cured resin:

[0139] S1, preparing a capping agent;

[0140] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0141] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0142] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0143] The reaction is carried out under stirring conditions.

[0144] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0145] The catalyst described in S1 is a composite catalyst, which includes T-12 catalyst and TEA, the molar ratio of the two is 1:1, and the amount of catalyst used is 200ppm based on the amount of IPDI.

[0146] The reaction described in S1, the reaction temperature is 60°C, and the reaction time is 1h.

[0147] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0148] The hyperbranched polyester polyol described in S2 is FE500, the dosage is 0.01 mol, and the end-capping agent added is IF, the addition amount is 0.19 mol.

[0149] The reaction described in S2 is carried out at a temperature of 50° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0150] The solvent in S2 is EOEOEA, and the added amount is 25%wt of the entire reaction system.

[0151] Example 9 (Based on Example 5) Preparation of hyperbranched polyurethane acrylate UV light-cured resin:

[0152] S1, preparing a capping agent;

[0153] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0154] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0155] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0156] The reaction is carried out under stirring conditions.

[0157] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0158] The catalyst described in S1 is a composite catalyst, which includes T-12 catalyst and TEA, the molar ratio of the two is 1:4, and the amount of catalyst used is 200ppm based on the amount of IPDI.

[0159] The reaction described in S1, the reaction temperature is 75°C, and the reaction time is 1h.

[0160] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0161] The hyperbranched polyester polyol described in S2 is FE500, the dosage is 0.01 mol, and the end-capping agent added is IF, the addition amount is 0.19 mol.

[0162] The reaction described in S2 is carried out at a temperature of 50° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0163] The solvent in S2 is EOEOEA, and the added amount is 25%wt of the entire reaction system.

[0164] Example 10 (Based on Example 5) Preparation of hyperbranched polyurethane acrylate UV light-cured resin:

[0165] S1, preparing a capping agent;

[0166] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0167] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0168] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0169] The reaction is carried out under stirring conditions.

[0170] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0171] The catalyst described in S1 is T-12 catalyst, and the dosage is 200ppm based on the dosage of IPDI.

[0172] The reaction described in S1, the reaction temperature is 30°C, and the reaction time is 3h.

[0173] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0174] The hyperbranched polyester polyol described in S2 is FE500, the dosage is 0.01 mol, and the end-capping agent added is IF, the addition amount is 0.19 mol.

[0175] The solvent in S2 is EOEOEA, and the added amount is 25%wt of the entire reaction system.

[0176] The reaction described in S2 is further carried out by adding 1,4-butanediol (BDO) in an amount of 8% of the molar weight of the hyperbranched polyester polyol.

[0177] The reaction in S2 has a reaction temperature of 80° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0178] Example 11 (Based on Example 5) Preparation of hyperbranched polyurethane acrylate UV light-cured resin:

[0179] S1, preparing a capping agent;

[0180] S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin;

[0181] The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or isocyanate ethyl acrylate.

[0182] The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

[0183] The reaction is carried out under stirring conditions.

[0184] The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:1.

[0185] The catalyst described in S1 is T-12 catalyst, and the dosage is 200ppm based on the dosage of IPDI.

[0186] The reaction described in S1, the reaction temperature is 30°C, and the reaction time is 3h.

[0187] The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

[0188] The hyperbranched polyester polyol described in S2 is FE500, the dosage is 0.01 mol, and the end-capping agent added is IF, the addition amount is 0.19 mol.

[0189] The solvent in S2 is EOEOEA, and the added amount is 25%wt of the entire reaction system.

[0190] The reaction described in S2 is further carried out by adding 1,4-butanediol (BDO) in an amount of 15% of the molar amount of the hyperbranched polyester polyol.

[0191] The reaction in S2 has a reaction temperature of 80° C. and a reaction time of 24-48 hours. The reaction is stopped after the disappearance of the isocyanate group NCO is detected.

[0192] The preparation process, products and UV light-cured resins of the hyperbranched polyurethane acrylates obtained in Examples 1-7 were tested and characterized:

[0193] (1) NCO content analysis

[0194] The NCO content was determined according to HG / T 2409-1992 using the toluene-di-n-butylamine method. (2) Thin layer chromatography analysis

[0195] The developing agent ratio was petroleum ether: ethyl acetate = 4:1, and the product was dissolved in ethyl acetate and then developed on a G silica gel plate. The G silica gel plate was activated in an oven at 110°C for 2 hours before use.

[0196] (3) FT-IR spectrum test

[0197] The infrared spectrum of the samples was measured using a Nicolet 5700 FT-IR instrument from Thermo Fisher Scientific, USA, with 32 scans and a scanning range of 4000-400 cm -1 , resolution 4cm -1 .

[0198] (4) 1H-NMR spectrum test

[0199] The AVANCE 400MHz nuclear magnetic resonance instrument of Bruker Company of Germany was used, and deuterated chloroform (CDCl3) or deuterated dimethyl sulfoxide (d-DMSO) was used as the solvent to prepare a solution with a concentration of 0.1g / mL, and tetramethylsilane (TMS) was used as the internal standard for testing.

[0200] (5) GPC test

[0201] The molecular weight and molecular weight distribution of PUA resin were determined by using a 1515 gel permeation chromatograph from Waters, USA. PS was used as the standard sample, THF was used as the mobile phase, the column temperature was 40°C, the flow rate was 1 mL / min, and the injection

[0202] The sample volume was 50 μL and the solution concentration was 5 mg / mL.

[0203] (6) Mass spectrometry (MS-ESI) test

[0204] The samples were measured using an ESI-high resolution time-of-flight mass spectrometer from Waters, USA, with tetrahydrofuran as the mobile phase and a flow rate of 1 mL / min. Only positive ion mode was used in the range of 100-4000 m / z. The samples were tested directly without any pretreatment.

[0205] (7) Viscosity test

[0206] The test was conducted using an NDJ-8S rotational viscometer. The PUA resin was added into the measuring cylinder of the rotational viscometer, and the temperature was raised and controlled within the range of 25±0.1°C to test the viscosity of the PUA resin.

[0207] (8) Water absorption test

[0208] Place the sample in an oven at 80°C and bake until constant weight, weigh it and record it as W0 (g), then place the sample in a disposable cup, add 50mL of deionized water to ensure that the sample is immersed; after soaking at room temperature for 7 days, take out the sample, quickly dry the surface water with filter paper, weigh it and record it as W1 (g), and the water absorption rate Wt is calculated as:

[0209]

[0210] (9) Gel content test

[0211] Cut the sample into small pieces of 2cm*2cm, dry them in an oven at 80℃ until constant weight, weigh them and calculate them as W0(g). Use N,N-dimethylformamide as solvent, wrap the sample with filter paper and place it in a sealed container to soak for 24 hours before taking it out. After taking it out, quickly use filter paper to absorb the surface solvent and weigh it, which is calculated as W1(g). The formula for calculating the gel content Mh is:

[0212]

[0213] (10) Pencil hardness test

[0214] The pencil hardness test was carried out according to standard ASTM D 3363, with a pencil load of 750 g and repeated twice.

[0215] (11) Adhesion test

[0216] The adhesion test was carried out according to the standard ASTM D 3359, using method B, i.e. the cross-cut method, with a cutting distance of 1 cm.

[0217] (12) Wear resistance test

[0218] The wear resistance of UV-cured resins was tested using a Taber abrader according to ISO 7784-1-2016. The loss of mass of the cured film after 100 rotations of wear at a load of 6N was measured, with grades ranging from B1 to B5 from best to worst.

[0219] (13) Scratch resistance test

[0220] According to the standard ISO 12137:1997, the scratch resistance of the cured film is tested by the pointed stylus method, and the scratch resistance is determined by gradually increasing the load on the stylus. The paint film is broken as the standard, the load range is 1-4kg, and 0.5kg is a variable value.

[0221] The FT-IR spectra of the hyperbranched polyurethane acrylate UV light-cured resin obtained in Examples 1-7 are shown in Fig. 9 The characteristic peaks of FT-IR spectrum are shown in Table 1, and the GPC curve is shown in Fig. 9 The molecular weight and its distribution are shown in Table 2.

[0222] Hyperbranched PUA was synthesized by converting the terminal hydroxyl groups of hyperbranched polyester polyol into terminal double bonds. The FT-IR spectra of hyperbranched PUA and its raw materials are shown in Figure 2. Figure 8 As shown, the main peaks are summarized in Table 1. Figure 8 It can be seen that the 2270 cm -1 The NCO characteristic peak at 1726 cm -1 The appearance of the C=O characteristic peak at 1531cm -1 The appearance of the CN characteristic peak at 1636cm indicates the formation of a carbamate bond; -1 With 810cm -1 The peak at is the characteristic peak of carbon-carbon double bond, which means that the carbon-carbon double bond structure is successfully integrated into the molecular structure of PUA. FT-IR test shows that the NCO in the end-capping agent reacts completely and reacts with the hyperbranched polyester polyol to form a hyperbranched PUA with a double bond structure.

[0223] Table 1 Characteristic peaks of the FT-IR spectra of the prepared series of hyperbranched PUAs

[0224]

[0225] Table 2 Molecular weight and distribution of hyperbranched PUA

[0226]

[0227] like Fig. 9As shown, the double peaks on the left of the GPC curve of PUA are PUA resins, and the single peak on the right is the peak of the mobile phase THF, so the peak has the same elution time in different samples. The molecular weight and its distribution listed in Table 2 are the measurement data of the double peaks on the left. It can be seen that the PUAs using the same end-capping agent have similar molecular weights and distributions and are both bimodal structures with small side peaks. The F500 series hyperbranched PUA has a larger molecular weight than the H500 series and AE500 hyperbranched PUAs, which is consistent with the fact that the molecular weight of the IF end-capping agent is greater than that of the IH end-capping agent. However, there is a large gap between the GPC test molecular weight of the hyperbranched series of substances and the theoretical molecular weight. This is because the testing principle of GPC is to separate according to the fluid volume of the polymer and then calculate according to the benchmark. When hyperbranched polymers flow, the polymer molecules are spherical and have the advantage of low viscosity. General GPC calibration materials are linear polymers, so the molecular weight of hyperbranched polymers cannot be calibrated. Therefore, the above GPC only examines the molecular weight distribution of hyperbranched polymers.

[0228] In summary, FT-IR and GPC tests show that the use of a single molecular weight distribution end-capping agent IH or IF reacted with a hyperbranched polyol to form a hyperbranched PUA with the expected structure and molecular weight distribution.

[0229] In order to avoid high crosslinking and gel curing in the synthesis of hyperbranched polyurethane acrylate, it is hoped to synthesize a monoisocyanate acrylate. To this end, thin layer chromatography and GPC analysis and testing methods were used in the synthesis to track the changes in raw materials and products during the synthesis process. The schematic diagram of the thin layer chromatography of the reaction system at the end of the reaction is shown in the figure below: Figure 3 As shown. Figure 3 It can be seen that at the end of the reaction, the difunctional IPDI has been completely reacted and converted into a monoisocyanate product, and the synthesis process has good reaction selectivity.

[0230] Figure 4 The GPC spectra of raw material IPDI, HEA and product IH. It can be seen from the figure that their peak positions are significantly different. On the GPC curve of product IH, no peaks of IPDI and HEA are seen. It is roughly concluded that the raw materials have been completely reacted and there is no IPDI and HEA residue. Since the GPC test uses di-n-butylamine to block NCO, the peak time of IPDI is shorter than that of IH.

[0231] The structures of the end-capping agents IH and IF and their raw materials were characterized by FT-IR and the changes of functional groups were studied. The FT-IR spectra are shown in Figure 5 As shown. The 1636cm -1 and 810cm -1The appearance of the characteristic peak of carbon-carbon double bond at 3423 cm -1 The disappearance of the stretching vibration peak of the hydroxyl group (OH bond), the appearance of the stretching vibration peak of the carbamate bond (NH bond) in IH and IF, and the 1531cm- 1 The stretching vibration peak of the carbamate group (CN bond) at 2270 cm-1 indicates that the hydroxyl groups in HEA and FM1D reacted completely with the NCO group of IPDI to form a carbamate bond. -1 The characteristic peak of NCO group appeared at , indicating that there were still active NCO groups in the end-capping agents IH and IF. In summary, according to the FT-IR spectra, the hydroxy acrylates HEA and FM1D reacted with IPDI to generate end-capping agents IH and IF with NCO groups and carbon-carbon double bond structures.

[0232] The nuclear magnetic resonance hydrogen spectrum can show the resonance effect of H in the capping agent in the resonance spectrum. Through the spectrum, the information of H in different chemical environments in the capping agent molecule can be obtained to determine the chemical structure of the sample. Figure 6 The peak area was normalized by taking the peak area of ​​H atom on carbon 2 as 1. 1 Each peak in the H-NMR spectrum was assigned, and the assignment results and peak areas are shown in Table 3. The nuclear magnetic hydrogen spectrum data of the synthetic product are shown in Table 3. The peak shape of each proton peak of the product is basically consistent with the peak shape of the theoretical reaction product, indicating the successful synthesis of the end-capping agent IH.

[0233] Table 3 IH 1 H-NMR assignment

[0234]

[0235]

[0236] IH was further analyzed using MS-ESI technology, and the results are as follows Figure 7 Assuming that the abundance intensity is independent of molecular weight, most of the components in the capping agent can be identified by molecular weight.

[0237] According to the MS-ESI ionization theory, the mass-to-charge ratio of possible ionization products was calculated and compared with Figure 7 The m / z of the peaks in the MS-ESI spectrum are compared, and the results are shown in Table 4. From the MS-ESI spectrum, it can be seen that the peak with a mass-to-charge ratio of 361.1742 corresponds to IH+Na +, indicating that the IH end-capping agent generated by the reaction of IPDI and HEA conforms to the theoretical calculated structure and has an ideal molecular mass. At the same time, there are no peaks near m / z=139 / 245 / 134 / 477 in the MS-ESI spectrum, indicating that there is no IPDI / HEA monomer or double end-capping reaction product of IPDI and IH in the end-capping agent IH, and the end-capping agent IH has a single molecular structure.

[0238] Table 4 Mass-to-charge ratio analysis of ionization products in IH

[0239]

[0240] In summary, HEA or FM1D and IPDI underwent a controllable chemical reaction using the above process, and end-capping agents IH and IF with controllable molecular structure and composition were synthesized.

[0241] The hyperbranched polyurethane acrylate obtained in Examples 1-7 was prepared into UV light-curable resin for performance testing:

[0242] The synthesized hyperbranched PUA was mixed evenly with 2 wt % of photoinitiator TPO as shown in Table 3, added into a clean brown glass bottle, placed in a 60° C. vacuum oven for degassing for 30 min, and sealed to obtain a hyperbranched PUA UV-curable resin.

[0243] Fix the prepared flat glass on a horizontal plane, and fix the hard plastic plate on the flat glass, use a coating rod with a gap of 0.25mm to coat the UV-curable PUA resin on the hard plastic plate, place the cured film in a 60℃ vacuum oven for leveling for 5 minutes, and then place the coating in a UV curing box for UV curing for 2 minutes to obtain a UV-cured film of hyperbranched polyurethane acrylate. The power of the high-pressure mercury lamp used for curing is 2kW and the wavelength is 365nm. The mechanical properties of the obtained cured film were tested. The surface appearance of the obtained UV-cured film is shown in Figure 2 , the formula is shown in Table 5.

[0244] Table 5 UV curing PUA resin formula

[0245]

[0246] The FT-IR spectrum of hyperbranched PUA after curing is as follows Figure 8 As shown, by observing 810cm -1 The double bond conversion rate of the hyperbranched PUA resin was studied by measuring the intensity change of the double bond characteristic peak at 1726 cm -1The characteristic absorption peak of carbonyl (C=O) was used as the internal standard because the intensity of the (C=O) peak in the FT-IR spectrum did not change much before and after curing. The absorption peak area was calculated using the integral function in the OMNIC software and the results are shown in Table 6.

[0247] Table 6 Double bond conversion rate of UV-cured PUA cured films

[0248]

[0249] As shown in Table 6, the use of active diluents can significantly improve the double bond conversion rate of the resin. This is because after vacuum degassing, the solvent butanone evaporates and the viscosity is high. The chain segment movement is difficult, which hinders the free radical polymerization, so the double bond conversion rate is low. After adding active diluents, the viscosity of the cured resin decreases, the chain segment is easier to move, and the double bond conversion is more thorough. The double bond conversion rate of H500 is increased from 74.39% to 96.73% of HE500. Therefore, even if the H500 and F500 cured films have the largest double bond content in the series, the gel content is lower than the cured film of the reactive diluent diluted resin.

[0250] The addition of ITH1000 to HNT1500 significantly increased the viscosity, hindered the polymerization reaction, and reduced the double bond conversion rate, making the HNT1500 cured film have the lowest crosslinking density.

[0251] After using EOEOEA, αAE500>αHE500>αFE500, and the AE500 sample has the highest double bond conversion rate and crosslinking density because of its minimum viscosity and good molecular regularity. Although FE500 resin has a lower viscosity than HE500 resin, the raw material FM1D used in the synthesis of IF has a side methyl structure, which not only destroys the regularity of the structure but also hinders the free radical polymerization, reducing the double bond conversion rate. The FE500 cured film has the lowest crosslinking density of 93.73%.

[0252] When the same end-capping agent is used, the sample diluted with EOEOEA has a lower viscosity than the sample diluted with NVP, and the diluent has a regular molecular structure, so it has a higher double bond conversion rate. However, the effect of EOEOEA plasticizer has a greater impact on the cross-linking density, reducing the gel content and cross-linking density of the EOEOEA diluted sample.

[0253] The two diluents DPHA and TA have a high double bond content. At the beginning of the curing reaction, a large number of double bonds are initiated to undergo free radical polymerization, the viscosity increases rapidly, the movement of molecular segments is hindered during the curing reaction, and it is difficult for free radicals to continue to initiate polymerization, resulting in a decrease in conversion rate. The double bond conversion rate of HED500 dropped to 88.34%, but the high double bond content of the two high-functionality diluents still improved the crosslinking density.

[0254] The surface properties of the PUA cured film, such as hardness, scratch resistance, abrasion resistance and adhesion, were tested to investigate the protectiveness of the hyperbranched PUA cured film to the attached substrate, and the test results are shown in Table 7. As can be seen from Table 7, the prepared hyperbranched PUA cured films all have a high pencil hardness, which is above 3H, among which the HN500 and AE500 cured films have the highest hardness of 8H.

[0255] Table 7 Surface properties of PUA cured films

[0256]

[0257] Note: The pencil hardness level is H-9H from low to high; the scratch resistance load range is 1-4kg, with 0.5kg as a variable value; the wear resistance test level is B1-B5 from good to bad; the adhesion test level is 5B-0B from good to bad.

[0258] When the same active diluent is used, the surface hardness changes with the different end-capping agents in the order of AE500>HE500>FE500. Because AE500 hyperbranched PUA has the smallest molecular weight, in the presence of the same mass fraction of active diluent, AE500 has the largest molar fraction and the highest cross-linking density, providing physical force support for the cured film, so the hardness of the AE500 film is the highest, reaching 8H; after the IF end-capping agent is modified with caprolactone, the molecular chain has higher flexibility and reduces the hardness of the cured film, and the hardness of the FE500 film is only 3H.

[0259] The flexible EOEOEA acts as a plasticizer, which reduces the hardness of the cured film. The surface hardness of FE500 drops from 4H of F500 film to 3H. NVP with a rigid structure and DPHA and TA with high double bond content can significantly improve the surface hardness of PUA cured film. The surface hardness of HN500 reaches 8H, and the hardness of HED500 increases from 4H to 6H.

[0260] High hardness brings excellent scratch resistance to the cured film. The scratch resistance level of the cured film is above 3.5kg. The HN500 and AE500 cured films have exceeded the highest standard of 4kg, which can effectively protect the substrate from scratches.

[0261] The wear resistance of PUA cured film is relatively poor, because excellent wear resistance requires not only high hardness but also excellent toughness of the cured film. The wear resistance of high-hardness AE500 film, HN500 film and high-flexibility FN500 film is improved compared with other cured films, but still cannot meet the requirements for high wear-resistant samples. In terms of active diluents, the use of EOEOEA reduces the hardness of the cured film, while the use of NVP reduces the flexibility of the cured film. If you want to further improve the wear resistance of the film, you can use EOEOEA and NVP in combination.

[0262] Hyperbranched PUAs all have a high content of strongly polar group urethane bonds, so hyperbranched PUA cured films can be tightly bonded to the substrate, and the adhesion level reaches the highest 5B level.

[0263] It can be seen that by using the method provided by the present invention to prepare hyperbranched PUA, the reaction product can be controllably adjusted through different formulations and reaction conditions. Furthermore, the mechanical properties of the resulting resin cured film can be controllably adjusted, and a resin cured film with high hardness, high adhesion and high wear resistance can be obtained in a directionally manner.

[0264] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0265] The present invention and its implementation methods are described above, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it and design methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. A hyperbranched polyurethane acrylate UV light-curing resin, characterized in that: The resin structure is shown in structural formula Ⅰ: Wherein, R' represents polydipentaerythritol, and the structure of R is one or more of the following structural formulas II, III, and IV:

2. A method for preparing a hyperbranched polyurethane acrylate UV light-curing resin as claimed in claim 1, characterized in that: The following steps are involved: S1, preparing a capping agent; S2, the end-capping agent reacts with the hyperbranched polyester polyol to generate a hyperbranched polyurethane acrylate UV light-curing resin; The end-capping agent includes IH shown in structural formula V or IF shown in structural formula VI or ethyl isocyanate acrylate:

3. The method for preparing the hyperbranched polyurethane acrylate UV light-curing resin according to claim 2, characterized in that: The preparation of the end-capping agent described in S1 specifically includes: mixing IPDI and the catalyst under an argon atmosphere, adding the end-capping agent HEA or the end-capping agent FM1D, and reacting to obtain the end-capping agent IH or the end-capping agent IF.

4. The method for preparing the hyperbranched polyurethane acrylate UV light-curing resin according to claim 3, characterized in that: The molar ratio of IPDI to the end-capping agent HEA or the end-capping agent FM1D in S1 is 1:(1-1.2).

5. The method for preparing the hyperbranched polyurethane acrylate UV light-curing resin according to claim 3, characterized in that: The catalyst in S1 is T-12 catalyst, and the dosage is 200-500ppm based on IPDI.

6. The method for preparing the hyperbranched polyurethane acrylate UV light-curing resin according to claim 3, characterized in that: In the reaction described in S1, the reaction temperature is 30-75°C and the reaction time is 3-4h.

7. The method for preparing the hyperbranched polyurethane acrylate UV light-curing resin according to claim 2, characterized in that: The reaction in step S2 specifically includes: dissolving the IH or IF obtained in step S1 into a solvent under an argon atmosphere, adding a hyperbranched polyester polyol, and heating the reaction to obtain a hyperbranched polyurethane acrylate UV light-curing resin.

8. The method for preparing the hyperbranched polyurethane acrylate UV light-curing resin according to claim 7, characterized in that: The amount of the hyperbranched polyester polyol described in S2 is equivalent to the added IH or IF.

9. The method for preparing the hyperbranched polyurethane acrylate UV light-curing resin according to claim 7, characterized in that: In the reaction of S2, the reaction temperature is 30-100°C and the reaction time is 24-48h.

10. The method for preparing the hyperbranched polyurethane acrylate UV light-curing resin according to claim 7, characterized in that: The reaction described in S2 is stopped after the disappearance of the isocyanate group NCO is detected.

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