WO2007071132A1

WO2007071132A1 - Supermolecular intercalation-structured uv absorber as well as its preparation method and use

Info

Publication number: WO2007071132A1
Application number: PCT/CN2006/001243
Authority: WO
Inventors: Xue Duan; Dianqing Li; Zhenjun Tuo
Original assignee: Beijing University Of Chemical Technology
Priority date: 2005-12-19
Filing date: 2006-06-08
Publication date: 2007-06-28
Also published as: CN1803901A; CN1333005C

Abstract

A supermolecular intercalation-structured UV absorber as well as its preparation method and use. The present invention is characterized by the UV absorber utilizing the property of the layered double hydroxides (LDHs), which may be intercalation-structured, intercalaring the 5-benzotriazolyl-4-hydroxy-3-sec-butylbenzenesulfonic acid (BZO) into the interlayer of the LDHs, and then obtaining a supermolecular intercalation-structured material in which BZO anion serves as interlayer guest molecule. The supermolecular intercalation-structured UV absorber has a formula as follow: [M2+1-xM3+x(OH)2](C16H16N3O4S)-x·mH2O, which has a absorbent ratio more than 90% to 280-370 nm UV light, remarkably increased thermal stability relative to that of the interlayer guest BZO, the obviously decomposing temperature of the interlayer matter of 450 . The UV absorber can be used for the anti-photoaging additive of the resins which are susceptible to light-oxygen degradation, such as polypropylene, polycarbonate, acrylonitrile-butadiene-styrene copolymer (ABS) and polyurethane.

Description

Supramolecular intercalation structure ultraviolet light absorber, preparation method and use thereof

Technical field

The winter invention relates to a supramolecular intercalation structure ultraviolet light absorber, a preparation method thereof and use of the ultraviolet light absorber. Background technique

Polyolefins and other high molecular polymers are prone to photochemical degradation under ultraviolet light, resulting in changes in physical properties such as reduced elasticity, brittleness, and loss of mechanical strength. 5-benzotriazolyl-4-hydroxy-3 ec-butylbenzenesulfonic acid (BZO) has a strong absorption of ultraviolet light, for 200 ~ Ultraviolet light in the 400nm band has a strong absorption effect. However, there are few reports on the research and application of this compound as a UV absorber in domestic and foreign literatures. Only when it is applied to the dyeing of wool or textiles or added to the pulp. Reports that inhibit paper yellowing. When the thermal stability of the compound was examined, it was found that the color changed from white to brown when heated to about 120 ° C, and the ultraviolet absorption ability was greatly weakened due to structural changes. If 5-benzotriazole-4-hydroxy-3-isobutyl-benzoic acid is used as the ultraviolet light absorber in the processing of the composite material, not only cannot absorb ultraviolet rays to exhibit light resistance due to the decomposition of the compound at high temperature. The aging effect will also cause severe staining and contamination of the composite article. In addition, 5-benzotriazole-4-hydroxy-3-isobutyl-benzene cross-acid is slightly soluble in water at room temperature, and is easily soluble in water after salt formation, and is resistant to extraction and washing resistance in composite materials. Both are poor and cannot be used efficiently for a long time. Therefore, if you want to use it as an ultraviolet light absorber for polymer plastic products, you must first improve its thermal stability.

Layered Double Hydroxides (LDHs) is an important new type of inorganic functional material. Due to its structure and composition control, it has become more and more widely used as a functional additive in rubber and plastic composite preparation. . LDHs have intercalation properties, and certain conditions can be substituted for new anions inserted between layers to replace the original anions, resulting in corresponding changes in structure and composition. The results show that the thermal stability of organic anions after inserting into the LDHs layer is greatly improved. High. The invention utilizes the exchangeability of interlayer ions of LDHs, inserts 5-benzotriazol-4-yl-3-isobutylxanthate anion into the interlayer of the LDHs precursor, and prepares a thermal stability and can be prepared. An intercalated structure ultraviolet light absorber that enhances the ability of the composite to resist ultraviolet light aging. The intercalated structure ultraviolet light absorbing agent acts as a shielding effect of ultraviolet light on the LDHs laminate and an ultraviolet light absorption effect of the 5-benzotriazole-4-hydroxy-3-isobutylbenzenesulfonic acid anion. The barrier capability of light will be further strengthened.

Qinglin He, Shu Yin, Tsugio Sato, "Synthesis and Photochemical Properties of Zinc-Aluminum Layered Double Hydroxide/Organic UV Ray Absorbing Molecule/Silica Nanocomposites", Journal of Physics and Chemistry of Solids, 65(12), 395-402 (2004) reported the preparation of six organic UV absorber intercalated hydrotalcite materials such as salicylic acid and sodium benzophenone sulfonate, which did not involve 5-benzotriazole-4-hydroxy-3-isobutyl -Benzenesulfonic acid, the thermal stability of any of the six intercalation products was not studied herein, and the six intercalation products were not used as the research contents of the ultraviolet light absorber of plastic products.

Document S. Guo, D. Li, W. Zhang, M. P, David GE, X. Duan, "Preparation of an anionic azo pigment-pillared layered double hydroxide and the thermo- and photostability of the resulting intercalated material", J Solid State Chem. 177, 4597-4604 (2004) The LDHs of the permanent red F5R intercalation were prepared and the thermal stability of the product was significantly improved. Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a supramolecular intercalation structure ultraviolet light absorber; another object of the present invention is to provide a method for preparing a supramolecular intercalation structure ultraviolet light absorber; The use of ultraviolet light absorbers.

The invention utilizes the performance of intercalation assembly of hydrotalcite, and intercalates between the hydrotalcite layers to assemble 5-benzotriazole-4-hydroxy-3-isobutyl-benzenesulfonic acid (BZO) anion (acid radical), and prepares The inter-layer guest is an intercalation structure material of BZO anion ((C ₁₆ H ₁₆ N ₃ 0 ₄ S) ^_ ).

The chemical composition of the supramolecular intercalation structure ultraviolet light absorber is:

[M ²⁺ ₁ ., M ³⁺ _x (OH) ₂ ](C _I6 H ₁₆ N ₃ 0 ₄ S)- _;c · m3⁄40 Where 0.2<; 0.33, m is the number of crystal water molecules in the layer, 0 < m <2;

M ²⁺ and M ³⁺ represent bivalent and trivalent metal ions, respectively, and M ²⁺ is any one of Mg ²⁺ , Ni ²⁺ , Zn ²⁺ , Fe ²⁺ and Cu ²⁺ , M ^{2 +} preferably Zn ²⁺ or Mg ²⁺ ; M ³⁺ is any one of Al ³⁺ , Co ³⁺ , Fe ³⁺ , Ti ³⁺ and Ga ³⁺ , and M ³⁺ is preferably Al ³⁺ . The molar ratio of M ²⁺ /M ³⁺ is 2-4:1.

The apparent decomposition temperature of the organic species between the layers of the ultra-molecular intercalation structure of the ultraviolet light absorber is about 450 ° C, and the ultraviolet light absorption rate of the 280-370 nm band is greater than 90%.

The specific preparation steps of the supramolecular intercalation structure ultraviolet light absorber are as follows:

A. Desorbing CO ₂ deionized water and hydrotalcite LDHs precursor respectively in a stirred reactor and thoroughly mixing and mixing a hydrotalcite precursor suspension having a concentration of 0.05-0.15 M;

The hydrotalcite precursor used is a hydrotalcite having an interlayer anion of NC or C0 ₃ ² — and its structural formula is: [Μ ²⁺ _1- Μ ³⁺ _χ (ΟΗ) ₂ ] [Ν0 ₃ · 3⁄40] or [M^ JV^+ OH ] [C0 ₃ ² - _x/2 . mB ₂ 0], where 0.2<x<0.33, m is the number of crystal water molecules in the layer, 0<m<2; M ²⁺ /M ³⁺ molar ratio 2-4:1; M ²⁺ is any one of divalent metal ions Mg ²⁺ , Ni ²⁺ , Zn ²⁺ , Fe ²⁺ and Cu ²⁺ , and M ²⁺ is preferably Zn ²⁺ or Mg ^{2 +} ; M ³⁺ is any one of the trivalent metal ions Al ³⁺ , Co ³⁺ , Fe ³⁺ , Ti ³⁺ and Ga ³⁺ , and M ³⁺ is preferably Al ³⁺ . The preparation method of hydrotalcite can be found in the patent CN99119385,7.

B. Using BZO and deionized C0 ₂ deionized water to prepare an aqueous solution with a concentration of 0.05-0.2M, completely dissolve BZO, and adjust the pH value of the solution to 3.5-8 with NaOH;

C. While rapidly stirring under nitrogen protection, add the BZO solution prepared in step B to the suspension in the reactor described in step A. The amount of BZO solution should be added to meet the molar number of BZO anions and the hydrotalcite precursor in the mixed system. The theoretical molar ratio of the BZO anions accommodated between the layers is 1-3:1, crystallized at a temperature of 25-100 ° C for 2-10 hours, filtered, washed, and dried to obtain a BZO intercalated hydrotalcite.

The XRD and IR characterizations of the intercalated hydrotalcites are shown (see Figures 1, 2). The anions have been assembled into the layered LDHs. According to TG-DTA analysis, the apparent decomposition temperature of BZO was 240 °C (see Figure 3), and the apparent decomposition temperature of the intercalated product increased to about 45 CTC (see Figure 4), and there was no obvious discoloration. The UV absorption curve measured by UV-vis shows that the UV absorption rate in the 280-370 nm band is greater than 90% (see Figure 5). The supramolecular intercalation structure ultraviolet light absorber of the present invention is sufficiently dispersed in a polypropylene, a polycarbonate, a polyurethane, a acrylonitrile-butadiene-styrene copolymer (ABS) by kneading, and then with no added photooxygen The pure material of the stable auxiliary agent was subjected to ultraviolet aging contrast experiment. Taking polypropylene as an example, the carbonyl peak (1730 cm ^-1 ) and the carboxyl group (3346 cm - ¹ ) peak representing the degree of photooxidation of polypropylene were compared by measuring the infrared spectrum. It was found that the BZO intercalated ultraviolet light absorber can significantly improve the aggregation. UV aging resistance of propylene, ABS and polyurethane resins (see Table 1).

The advantages of the invention are:

1. The first intercalation preparation gave a hydrotalcite material in which the interlayer anion was monovalent 5-benzotriazole-4-hydroxy-3-isobutyl-benzenesulfonate ion.

2. The thermal stability of the intercalated structure UV absorber is significantly higher than that of the intercalation guest BZO itself. The apparent decomposition temperature is increased to about 450 °C, which can be used as polypropylene, acrylonitrile-butadiene- An anti-ultraviolet aging additive for oxy-degradable polymer materials such as styrene copolymer (ABS).

3. This intercalated structure UV absorber has an ultraviolet absorption rate of more than 90% in the 280-370nm range and excellent UV absorption.

4. Due to the selective ion exchange characteristics of hydrotalcite, the prepared ultraviolet light absorber does not contain heavy metal impurities introduced during the synthesis of general organic ultraviolet absorbers, which can further improve the stability of the composite. DRAWINGS

1 is an XRD pattern of the hydrotalcite precursor and the BZO anion intercalation ultraviolet light absorber in Example 1, wherein: a is an XRD spectrum of the hydrotalcite precursor, and b is an XRD of the intercalated ultraviolet absorber. Spectrum.

2 is an infrared spectrum of the hydrotalcite precursor, BZO and BZO anion intercalating ultraviolet light absorber in Example 1, wherein: a is an infrared spectrum of the hydrotalcite precursor, b is an infrared spectrum of BZO, c It is an infrared Pan map of BZO anion intercalated UV absorber.

Figure 3 shows the TG-DTA curve of BZO. 4 is a TG-DTA curve of the BZO anion intercalation ultraviolet light absorber in Example 1. 5 is an ultraviolet absorption curve of BZO and BZO anion intercalating ultraviolet light absorber in Example 1, wherein: a is an absorption curve of BZO; and b is an absorption curve of a BZO anion intercalating ultraviolet light absorber. DETAILED DESCRIPTION OF THE INVENTION Example 1:

Step A: 35.7 g (0.12 mol) of solid Zn( 0 ₃ ) ₂ · 6H ₂ 0 and 22.5 g (0.06 mol) of solid A1(N0 ₃ ) ₃ · 9H ₂ 0 are dissolved in deionized water except C0 ₂ to prepare 150 ml of mixed salt solution; 14.4 g (0.36 mol) of solid NaOH was dissolved in deionized water except CO ₂ to prepare 150 ml of an alkali solution. The alkali solution and the salt solution were quickly nucleated in a full back-mixed rotary liquid membrane reactor at room temperature, and the resulting slurry was crystallized at 100 ° C for 6 h. After centrifugation, the precipitate was washed and the pH of the wash water was close to 7, and finally dried at 70 Torr for 24 h to obtain ZnAl-N0 ₃ -LDHs, which Ζη ²⁺ /Α1 ³⁺ = 2:1.

The ZnAl-N0 ₃ -LDHs precursor C0 ₂ well dispersed in de-ionized water to prepare a 0.10M suspension.

Step B: BZO was dissolved in de-C0 ₂ deionized water at room temperature to prepare a 0.15 M aqueous solution, and NaOH was added to adjust pH = 7.

Step C: Under nitrogen protection and rapid stirring, the solution prepared in Step B is added to the suspension prepared in Step A at a volume ratio of 1:1, reacted at 100 ° C for 2 hours, filtered, and washed to a pH of about 7, 70 ° C. After drying for 24 hours, a BZO anion intercalated ultraviolet light absorber was obtained. The chemical composition of the product was determined by elemental ICP analysis to be Zn. ₆₇ Alo. ₃₃ (OH) ₂ (C ₁₆ H ₁₆ N ₃ 0 ₄ S). . ₃₃ · 0.64H ₂ O.

According to XRD and infrared analysis (see Fig. 1, Fig. 2), the spacing of the hydrotalcite layer increased from 0.89 to 2.32 nm, and the inter-layer nitrate disappeared, and there is obvious evidence that it is between the sulfonic acid group and the hydrotalcite layer. There are new keys formed. It can be concluded that the BZO anion has been inserted between the hydrotalcite layers, and there is a strong interaction between the host and the guest, forming a supramolecular intercalation structure, which is not a simple physical mixture between the host and the guest. According to TG-DTA analysis, BZO anion intercalated ultraviolet light absorber interlayer The apparent decomposition temperature of the species is about 450. C (see Figure 4). The UV-vis test (see Figure 5) showed that the maximum absorption peak appeared at 365 nm with an absorbance of 92%. Example 2:

Step A: A hydrotalcite suspension was prepared as in Example 1.

Step B: BZO off C0 ₂ was dissolved in deionized water to prepare a 0.10M aqueous solution having a pH of 3.5.

Step C: Rapid stirring under nitrogen protection while adding the BZO solution prepared in Step B to the suspension prepared in Step A at a volume ratio of 1:1, reacting at room temperature for 10 hours, filtering, washing to pH of about 7, and drying at 70 ° C. In hours, a BZO anion intercalated ultraviolet light absorber was obtained. The chemical composition of the product was obtained by elemental ICP analysis as Zn ₇ oAl ₃ o(OH) ₂ (C ₁₆ H ₁₆ N ₃ 0 ₄ S)o. ₃ o ■ 0.95H ₂ O. The test found that the maximum absorption peak appeared at 357 nm and the absorption rate was 90%. Example 3:

Prepared according to Example 1 aqueous suspensions of talc embodiment, the C0 ₂ removal BZO was dissolved in deionized water to prepare an aqueous 0.15M NaOH was added to adjust pH = 8. The precursor suspension and the BZO solution were mixed at a volume ratio of 1:2 according to the method of Example 1, and reacted at 10 CTC for 6 hours, filtered, washed to a pH of about 7, and dried at 70 ° C for 24 hours to obtain BZO anion intercalated ultraviolet light. Absorbent. The chemical composition of the product was analyzed by elemental ICP as Zn ₀ . _6s Al ₀ . ₃₂ (OH) ₂ (C ₁₆ H ₁₆ N ₃ O ₄ S) ₀ . ₃₂ · 1.083⁄4 Ο. The test found that the maximum absorption peak appeared at 335 nm and the absorption rate was 91%. Example 4:

A hydrotalcite of MgAl-N0 ₃ -LDHs and Mg ²⁺ /Al ³⁺ =2:1 was selected as a precursor to prepare a 0.10 M suspension.

In the same manner as in Example 1, a 0.10 M BZO solution was prepared, and the volume ratio of the precursor suspension to the BZO solution was 1:3 to obtain a BZO anion intercalating ultraviolet light absorber. The chemical composition of the product was determined by elemental ICP analysis to be Mg ₆₇ Al. . ₃₃ (OH) ₂ (C ₁₆ H ₁₆ N ₃ 0 ₄ S) _a33 · 0.72H ₂ O. The test found that the large absorption peak appeared at 350 nm and the absorption rate was 93%. The apparent decomposition temperature of the ultraviolet light absorber inter-layer species is greater than 400 °C. Example 5:

The MgAl-N0 ₃ -LDHs hydrotalcite was selected as the precursor, and Mg ²⁺ /Al ³⁺ = 2: 1 was prepared to prepare a 0.15 M suspension. In the same manner as in Example 1, a 0.20 M BZO solution was prepared and mixed with a volume ratio of the precursor suspension to the BZO solution of 1:1.5 to obtain a BZO anion intercalating ultraviolet light absorber. The chemical composition of the product was determined by elemental ICP analysis to be Mg wAl ^OHMCwH Ns ^S)^ 0.85H ₂ O. The test found that the maximum absorption peak appeared at 345 nm and the absorption rate was 90%. The apparent decomposition temperature of the inter-layer species was not determined. Application example:

The BZO anion intercalated ultraviolet light absorber prepared in Example 1-5 was added to polypropylene and ABS resin at a shield ratio of 1%, and irradiated for 60 minutes under an ultraviolet lamp having a wavelength of 250-380 nm and a power of 1000 W, at intervals of 10 Flip 1 minute. The tensile strength was tested according to GB/T1040-1992. The results are shown in Table 1.

The BZO anion intercalation ultraviolet light absorber prepared in Example 1-5 was added to the polyurethane resin at a shield ratio of 1%, and was irradiated for 60 minutes under a UV lamp having a wavelength range of 250-380 nm and a power of 1000 W, and inverted at intervals of 10 minutes. Times. The tensile strength was tested according to GB/T528-98. The results are shown in Table 1.

Table 1 Spline tensile strength test results (MPa) UV absorbers polypropylene ABS polyurethane spline state

None 31.04 53.59 9.47 Before UV irradiation

None 11.14 25.71 4.09 After UV irradiation

Example 1 Preparation 27.36 48.33 8.56 After UV irradiation

Example 2 Preparation 28.12 47.52 9.27 After UV irradiation

Example 3 Preparation 27.83 49.05 8.83 After UV irradiation

Example 4 Preparation 27.19 47.21 8.04 After UV irradiation

Example 5 Preparation 27.04 46.47 8.21 After UV irradiation

Claims

Claim

1 . A supramolecular intercalation structure ultraviolet light absorber having a chemical composition formula of: [M ²⁺ _1- , M ³⁺ , (OH) ₂ ](C ₁₆ H ₁₆ N ₃ 0 ₄ S)-, M3⁄40

Where 0.2 <x < 0.33, the number of molecules of water in the layer, 0 / w 2;

M ²⁺ and M ³⁺ represent bivalent and trivalent metal ions, respectively, and M ²⁺ is any one of Mg ²⁺ , Ni ²⁺ , Zn ²⁺ , Fe ²⁺ and Cu ²⁺ , M ^{3 +} is any one of Al ³⁺ , Co ³⁺ , Fe ³⁺ , Ti ^{3+ ,} and Ga ³⁺ .

2. The supramolecular intercalation structure ultraviolet light absorber according to claim 1, wherein the organic decomposition temperature of the interlayer organic layer is about 450 ° C, and the ultraviolet absorption of the 280-370 nm wavelength band is greater than 90%.

3. The supramolecular intercalation structure ultraviolet light absorber according to claim 1, wherein M ²⁺ is Zn ²⁺ or Mg ²⁺ , and M ³⁺ is Al ³⁺ .

4. A method for preparing a supramolecular intercalation structure ultraviolet light absorber, the specific steps are as follows:

A. Deionized water and hydrotalcite LDHs precursors were separately added to the stirred reactor and mixed thoroughly to prepare a hydrotalcite precursor suspension with a concentration of 0.05-0.15M;

B. Using BZO and deionized water to prepare an aqueous solution with a concentration of 0.05-0.2M, and adjusting the pH of the solution with NaOH to 3.5-8;

C. Under the condition of nitrogen protection and rapid stirring, add the BZO solution prepared in step B to the suspension of the step A reactor. The amount of BZO solution should be added to the molar ratio of BZO anion in the system after mixing and the hydrotalcite precursor layer. The theoretical molar ratio of the BZO anion can be accommodated to be 1-3:1, crystallized at a temperature of 25-100 ° C for 2-10 hours, filtered, washed, and dried to obtain a BZO anion intercalated hydrotalcite.

The method for preparing a supramolecular intercalation structure ultraviolet light absorber according to claim 4, wherein the talc precursor is a hydrotalcite having an interlayer anion of NC or C0 ₃ ^2_ , and the structural formula is: Μ ²⁺ _1-χ Μ ³⁺ _χ (ΟΗ) ₂ ] [N0 ₃ ", ' H ₂ 0] or [M^JV^+ OH ] [C0 ₃ ² ", / ₂ -mH ₂ 0], Wherein 0.2 x < 0.33, m is the number of crystal water molecules in the layer, 0 <2; M ²⁺ / M ^{3 +} molar ratio is 2-4 : 1 ; M ²⁺ is divalent metal ions Mg ²⁺ , Ni ²⁺ Any one of Zn ²⁺ , Fe ^{2+ ,} and Cu ²⁺ ; M ³⁺ is any one of trivalent metal ions Al ³⁺ , Co ³⁺ , Fe ³⁺ , Ti ^{3+ ,} and Ga ³⁺ .

The method for preparing a supramolecular intercalation structure ultraviolet light absorber according to claim 5, wherein M ²⁺ is Zn ²⁺ or Mg ²⁺ , and M ³⁺ is Al ³⁺ .

The use of the supramolecular intercalation structure ultraviolet light absorber according to any one of claims 1 to 3 as a photo-aging additive in an azo-degradable polymer.

The use of the supramolecular intercalation structure ultraviolet light absorber according to any one of claims 1 to 3 as a photo-aging additive in polypropylene, polycarbonate, polyurethane or ABS plastic.