Method for preparing organopolysiloxane resins

Abstract

A method for preparing organopolysiloxane resins, including the steps below: (1) using an alkoxysilane, a capping agent and an acidic compound as raw materials; (2) mixing all the raw materials uniformly, and the capping agent, the alkoxysilane and the acidic compound have a mole ratio from 0 to 40:1:0.2 to 5; (3) performing a polycondensation reaction at a temperature of 40-150 C. in 2-20 h; (4) adjusting the reaction product to neutral, and obtaining a product of organopolysiloxane resin after purification. Preparation of organopolysiloxane resins with the present application method has benefits on less environmental pollution, low energy consumption, efficient productivity, high yield of silicone resin with excellent performance.

Claims

1. A method for preparing organopolysiloxane resins, comprising the following steps: (1) using an alkoxysilane, a capping agent and an acidic compound as raw materials without adding water; (2) mixing all the raw materials uniformly, wherein the capping agent, the alkoxysilane and the acidic compound have a molar ratio from more than 0 to 40:1:0.2 to 5; (3) performing a polycondensation reaction at a temperature of 40-150 C. in 2-20 h to obtain a reaction product; (4) adjusting the reaction product to neutral, and obtaining a product of organopolysiloxane resin after purification; wherein the acidic compound comprises an acidic compound I containing a carboxyl group; and wherein a molar ratio of the carboxyl group to an alkoxy group contained in the alkoxysilane is 0.2-5:1.

2. The method for preparing organopolysiloxane resins of claim 1, wherein the alkoxysilane comprises at least one of Q unit, D unit or T unit; and the capping agent comprises a M unit.

3. The method for preparing organopolysiloxane resins of claim 2, wherein a molar ratio of the M unit and a sum of the Q unit, the T unit and the D unit is from more than 0 to 40:1.

4. The method for preparing organopolysiloxane resins of claim 2, wherein the alkoxysilane comprises one or more silanes selected from the group consisting of methyl orthosilicate, ethyl orthosilicate, methyl polysilicate ester, ethyl polysilicate, methyl trimethoxysilane, methyl triethoxysilane, ethyl trimethoxysilane, ethyl triethoxysilane, propyl triethoxysilane cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, triethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, allyl triethoxysilane, phenyl trimethoxysilane, phenyl triethoxysilane, dimethyl dimethoxy silane, dimethyl diethoxysilane, methyl ethyl dimethoxysilane, methyl ethyl diethoxysilane, propyl methyl dimethoxy silane, propyl methyl diethoxysilane, methyl dimethoxy silane, methyl diethoxysilane, allyl methyl dimethoxy silane, allyl methyl diethoxysilane, diphenyl dimethoxy silane, diphenyl diethoxysilane, methyl phenyl dimethoxy silane, methyl phenyl diethoxysilane, acryloxytrimethoxysilane, acryloxy propyl triethoxysilane, methacryloxy propyl dimethoxysilane, methacryloxy propyl diethoxysilane, C4-C20 alkyl trimethoxysilane, C4-C20 alkyl triethoxysilane, -chloropropyltrimethoxysilane, -chloropropyltriethoxysilane, mercapto propyl trimethoxysilane, and mercapto propyl triethoxysilane.

5. The method for preparing organopolysiloxane resins of claim 2, wherein the capping agent comprises one or more selected from the group consisting of 1, 1, 1, 3, 3, 3-hexamethyl disiloxane, 1, 1, 3, 3-tetramethyl disiloxane, 1, 1, 3, 3-tetramethyl-1, 3-divinyldisiloxane, 1, 1, 3, 3 tetramethyl 1, 3-diphenyl disiloxane, 1, 3-dimethyl-1, 1, 3, 3-tetraphenyldisiloxane, 1, 1, 1, 3, 3, 3, 5, 5, 7, 7, 7-decamethyltetrasiloxane, 1, 1, 3, 3, 3-pentamethyl disiloxane, and 1, 1, 1, 3, 5, 5, 5 heptamethyltrisiloxane.

6. The method for preparing organopolysiloxane resins of claim 2, wherein the capping agent is a silane containing a single chlorine/alkoxy group; and wherein the silane comprises one or more selected from the group consisting of trimethylsilyl chloride, trimethylmethoxysilane, trimethylethoxysilane, dimethyl vinyl chlorosilane, vinyl dimethyl methoxysilane, vinyl dimethyl ethoxysilane, and dimethylchlorosilane.

7. The method for preparing organopolysiloxane resins of claim 1, wherein the acidic compound I comprises one or more selected from the group consisting of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, oxalic acid, benzoic acid, C6-C26 monocarboxylic acid, succinic acid, adipic acid, and phthalic acid.

8. The method for preparing organopolysiloxane resins of claim 1, wherein the alkoxy group comprises methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, and isobutoxy.

9. The method for preparing organopolysiloxane resins of claim 1, wherein the alkoxy group comprises ethylene glycol monomethyl ether and ethylene glycol monoethyl ether.

10. The method for preparing organopolysiloxane resins of claim 1, wherein the acidic compound further comprises an acidic compound II, an amount of the acidic compound II of total raw materials is 0.1-5 wt %.

11. The method for preparing organopolysiloxane resins of claim 10, wherein the acidic compound II comprises one or more selected from the group consisting of: sulfuric acid, hydrochloric acid, phosphoric acid, trifluoromethane sulfonic acid, p-toluenesulfonic acid, ferric chloride, aluminum chloride, zinc chloride, titanium tetrachloride, tin dichloride, solid super acid, acid clay, and cation exchange resin.

12. The method for preparing organopolysiloxane resins of claim 1, wherein the acidic compound further comprises an acidic compound III, an amount of the acidic compound III 1-50 wt % of an amount of the acidic compound II.

13. The method for preparing organopolysiloxane resins of claim 12, wherein the acidic compound III comprises one or more selected from the group consisting of: acetic anhydride, succinic anhydride, phthalic anhydride, phosphorus pentoxide, and organic acid chloride.

14. The method for preparing organopolysiloxane resins of claim 1, wherein the step (2) requires a mixing of the raw materials in 30-60 mins.

15. The method for preparing organopolysiloxane resins of claim 1, wherein the step (4), applies an aqueous solution of an alkaline compound to adjust the reaction product to neutral, the alkaline compound comprises one or more selected from the group consisting of: sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, ethylene diamine, ethanolamines, and triethylamine.

16. The method for preparing organopolysiloxane resins of claim 1, wherein a purification process of a neutralized product of the step (4) is as below: (4.1) separating an oil phase, drying the oil phase out, filtrating, obtaining a mixture of organopolysiloxane resin and volatile components; (4.2) obtaining an organopolysiloxane resin after separating the volatile components by vacuum distillation.

17. The method for preparing organopolysiloxane resins of claim 16, wherein the vacuum distillation is carried out at a temperature of 100-160 C.

18. The method for preparing organopolysiloxane resins of claim 1, wherein a structure of the organopolysiloxane resin is one unit composition selected from the group consisting of: MQ resin, MT resin, DT resin, MDT resin, MTQ resin, DTQ resin, MDTQ resin, and MD resin.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 is comparison of Infrared spectroscopy scan between the conventional method and the present application method for preparing MQ resin (M/Q=0.65).

DETAILED DESCRIPTION OF THE EMBODIMENTS

(2) Embodiments of the present application are described in further detail.

(3) The present application may be further illustrated in the following example embodiment, but examples are not limiting the scope of the present application.

Example 1

(4) Amount of reactants are shown in Table 1, the reaction conditions are listed in Table 2, the silane monomer and type I acidic compound were added to the reactor and stirred for 15 minutes, then acidic compound class II and class III acidic compound were added to the mixture, after stirring for 30 minutes, react for (reaction time) at the (reaction temperature), the mixture was cooled down to room temperature, washed with aqueous sodium carbonate and separated, the upper layer was distillated under reduced pressure, to yield a polyorganosiloxane resin containing various functional groups, the results were shown in table 3 below.

(5) TABLE-US-00001 TABLE 1 Formulation List of All Examples Example(Units Composition) 1 2 3 4 5 Reagent MT HS-MT Ph-MT H-Ph-MT Vi-Ph-MT -HSC.sub.3H.sub.6Si(OEt).sub.3 142.8 EtSi(OEt).sub.3 192.0 PhSi(OEt).sub.3 288.0 240.0 PhSi(OMe).sub.3 267.3 ViMe.sub.2SiOSiMe.sub.2Vi 16.7 HMe.sub.2SiOSiMe.sub.2H 33.5 Me.sub.3SiOSiMe.sub.3 243.0 72.9 32.4 21.9 Acidic Compound Formic acid 208.7 I Acetic acid 216.0 155.5 198.0 Propionic acid 293.0 Acid Compound Hydrochloric acid 23.8 15.0 II Phosphoric acid 5.1 4.8 Trifluoromethane 2.2 sulfonic acid Acid Compound Acetic anhydride 6.0 0.5 3.0 1.0 III Succinic anhydride 1.0 Aqueous solution of Na.sub.2CO.sub.3, 7.5 wt % 140.4 385.7 414.5 445.0 361.1 Example(Units Composition) 6 7 8 9 10 Reagent MD MDT Ph-MDT H-Ph-MDT Vi-Ph-MDT MeSi(OEt).sub.3 89.0 PhSi(OEt).sub.3 252.0 PhSi(OMe).sub.3 326.7 198.0 Me.sub.2Si(OEt).sub.2 37.0 25.9 Me.sub.2Si(OMe).sub.2 335.0 36.9 33.5 ViMe.sub.2SiOSiMe.sub.2Vi 32.6 HMe.sub.2SiOSiMe.sub.2H 33.5 Me.sub.3SiOSiMe.sub.3 40.5 121.5 44.6 Acidic Compound Formic acid 241.5 265.7 185.2 I Acetic acid 144.0 231.0 Acid Compound Phosphoric acid 5.9 II Trifluoromethane 2.5 6.4 2.7 3.1 sulfonic acid Acid Compound Acetic anhydride 1.2 0.6 0.6 III Succinic anhydride 1.3 0.5 Aqueous solution of Na.sub.2CO.sub.3, 7.5 wt % 224.5 362.5 264.8 364.2 301.3 Example(Units Composition) 11 12 13 14 15 Reagent MQ-1 MQ-2 MQ-3 H-MQ Vi-MQ Si(OEt).sub.4 262.5 225.0 180.0 208.0 124.8 ViMe.sub.2SiOSiMe.sub.2Vi 15.7 HMe.sub.2SiOSiMe.sub.2H 50.3 Me.sub.3SiOSiMe.sub.3 87.9 82.6 77.8 58.2 Acidic Compound Acetic acid 231.0 207.0 172.8 264.0 172.8 I Hydrochloric acid 10.9 Acid Compound Phosphoric acid 6.5 II Trifluoromethane 3.5 2.6 2.6 sulfonic acid Acid Compound Acetic anhydride 0.7 1.3 0.5 1.6 III Succinic anhydride 0.7 Aqueous solution of Na.sub.2CO.sub.3, 7.5 wt % 305.1 454.4 431.3 335.3 561.0 Example(Units Composition) 16 17 18 19 20 21 Reagent MDQ Vi-MDQ MTQ Vi-MTQ MDTQ Vi-MDTQ Si(OEt).sub.4 112.5 150.0 Si(OMe).sub.4 150.0 124.8 76.0 91.2 MeSi(OMe).sub.3 77.0 27.7 38.5 27.7 Me.sub.2Si(OEt).sub.2 55.5 74.0 Me.sub.2Si(OMe).sub.2 30.0 36.0 ViMe.sub.2SiOSiMe.sub.2Vi 9.3 11.2 11.2 HMe.sub.2SiOSiMe.sub.2H Me.sub.3SiOSiMe.sub.3 45.6 56.7 60.8 29.2 28.4 29.2 Acidic Compound Formic acid 165.6 193.2 162.3 179.4 179.1 I Acetic acid 162.0 Acid Compound Hydrochloric acid 10.7 II Phosphoric acid 4.6 6.1 Trifluoromethane 2.1 1.9 1.7 sulfonic acid Acid Compound Acetic anhydride 0.5 0.5 1.6 III Succinic anhydride 0.9 1.2 0.4 Aqueous solution of Na.sub.2CO.sub.3, 7.5 wt % 401.7 452.8 538.1 516.8 438.9 362.2

(6) TABLE-US-00002 TABLE 2 Process Specification List of All Examples Process Specification Example(Units Reaction Reaction Vacuum Distillation Composition) Temperature/ C. Time/hr Temperature/ C. HS-MT 65 3.5 120 MDQ 70 3.5 120 MTQ 60 5 100 MDTQ 65 4 100 Vi-MQ 60 4.5 120 Vi-MDQ 65 5 105 Vi-MTQ 60 5 100 Vi-MDTQ 64 6 100 H-MQ 72 3 120 MT 60 3 120 MD 60 3 100 MDT 60 3.5 120 Ph-MT 70 6 120 Ph-MDT 75 5 105 H-Ph-MT 65 8 120 H-Ph-MDT 70 5 100 Vi-Ph-MT 65 6 100 Vi-Ph-MDT 70 5 120 MQ-1 70 5 120 MQ-2 72 5 120 MQ-3 70 5 120

(7) TABLE-US-00003 TABLE 3 Results of All Examples Results M.sub.n/ .sup.25/ CH.sub.2CH/ (SiH)H/ SH/ Example Yield/% Volatile/% g .Math. mol.sup.1 mPa .Math. s n.sub.D.sup.25 wt % wt % mmol .Math. g.sup.1 HS-MT 92.3 1.1 20.0 1.4450 4.0 MDQ 97.6 0.3 1924.6 MTQ 98.1 0.2 2037.5 MDTQ 97.5 0.4 1986.3 Vi-MQ 90.2 0.6 1265.0 3.8 Vi-DQ 93.9 0.4 2691.3 1.5 Vi-MTQ 95.2 0.7 2755.0 3.5 Vi-MDTQ 94.4 0.8 2887.3 2.7 H-MQ 98.9 0.2 2732.3 0.6 MT 98.0 1.1 35.0 MD 96.2 1.4 125.0 MDT 93.5 0.9 35.0 Ph-MT 95.2 0.4 2237.6 1.5435 Ph-MDT 96.3 0.4 1195.3 1.5310 H-Ph-MT 97.7 0.8 2188.4 1.5125 0.3 H-Ph-MDT 95.4 0.8 2084.4 1.5020 0.2 Vi-Ph-MT 98.7 0.4 2258.7 1.5478 2.2 Vi-Ph-MDT 97.7 0.4 2127.9 1.5315 5.0 MQ-1 98.6 0.1 4552.0 MQ-2 98.1 0.2 4775.0 MQ-3 97.9 0.5 3299.0

Comparative Example 1 (MQ-4)

(8) 300 g ethyl polysilicate, 100.44 g hexamethyldisiloxane and 110.22 g toluene were added into a 1 L three-necked flask, stirred and added a mixture of 30 g alcohol and 10.97 g concentrated hydrochloric acid, stirred and added 220.44 g purified water by dropwise in about 65 mins, then the mixture was heated to 72 C. and reacted for 3 h. The resultant was extracted by adding 110.22 g toluene, separated. 22.04 g 5 wt % KOH aqueous solution was added to the organic layer and heated to 72 C. and reacted for 6 h. The resultant was neutralized, dried, filtrated and concentrated at 160 C. under reduced pressure to give 135.53 g products, with yield 61.48%, volatile content 0.68%, M.sub.n 3370 g/mol.

Comparative Example 2 (MQ-5)

(9) 300 g ethyl polysilicate, 100.44 g hexamethyldisiloxane and 150.08 g toluene were added into a 1 L three-necked flask, stirred and added a mixture of 30 g alcohol and 11.24 g concentrated hydrochloric acid, stirred and added 126.36 g purified water by dropwise in about 68 mins, then the mixture was heated to 72 C. and reacted for 3 h. The resultant was extracted by adding 150.08 g toluene, separated. 23.02 g 5 wt % KOH aqueous solution was added to the organic layer, heated to 72 C. and reacted for 6 h. The resultant was neutralized, dried, filtrated and concentrated at 160 C. under reduced pressure to give 156.81 g product, with yield 68.13%, volatile content 0.75%, M.sub.n 3022 g/mol.

Comparative Example 3 (MQ-6)

(10) 300 g ethyl polysilicate, 129.6 g hexamethyldisiloxane and 120 g toluene were added into a 1 L three-necked flask, stirred and added a mixture of 30 g alcohol and 11.77 g concentrated hydrochloric acid, stirred and added 129.6 g purified water by dropwise in about 72 mins, then the mixture was heated to 72 C. and reacted for 3 h. The resultant was extracted by adding 129.6 g toluene, separated. 24.96 g 5 wt % KOH aqueous solution was added to the organic layer and heated to 72 C. and reacted for 6 h. The resultant was neutralized, dried, filtrated and concentrated at 160 C. under reduced pressure to give 135.53 g products, with yield 83.00%, volatile content 0.78%, M.sub.n 2173 g/mol.

(11) Comparison of Technical Specification between the present application method and the conventional method of synthesizing organopolysiloxane resin is shown in Table 4.

(12) TABLE-US-00004 TABLE 4 Comparison of Technical Specification between the present invention method and the conventional method of synthesizing organopolysiloxane resins M/Q = 0.62 M/Q = 0.68 M/Q = 0.80 Specification MQ-1 MQ-4 MQ-2 MQ-5 MQ-3 MQ-6 Yieldt/% 98.61% 61.48% 98.11% 68.13% 97.86% 83.00% Volatile 0.12% 0.68% 0.21% 0.75% 0.54% 0.78% Content/wt % M.sub.n 4552 3370 4775 3022 3299 2173 NOTE: M.sub.n means number average molecular weight, in units of g/mol, is measured by GPC; testing condition of the volatile component is 150 C. 3 h.
NOTE: M.sub.n means number average molecular weight, in units of g/mol, is measured by GPC. Testing condition of the volatile component is 150 C.3 h.

(13) From table 4 we can find that with the same M/Q ratio, the MQ resins prepared with the present application method has a higher yield of resin, less volatile and larger average molecular weight, when compared with MQ resins prepared with the traditional method.

(14) With the same M/Q ratio of 0.62, the MQ resin prepared with the present application method, namely MQ-1, has a 98.61% yield of resin, 0.12 wt % volatile content, 4552 g/mol number average molecular weight, meanwhile, the MQ resin prepared with the traditional method, namely, MQ-4, has a 61.48% yield of resin, 0.68 wt % volatile content, 3370 g/mol number average molecular weight.

(15) Infrared spectroscopy of MQ resin prepared respectively with the conventional methods and the present application method is shown in FIG. 1.

(16) From the FIG. 1, it can be found: in a wavelength range of 500-3200 cm.sup.1, the infrared spectra of MQ resin prepared respectively with the conventional methods and the present application method has no significant difference in the characteristic absorption peak of SiOSi (1080 cm.sup.1), SiCH.sub.3 (1260 cm.sup.1), CH (2960 cm.sup.1). We know the range of 3400-3700 cm.sup.1 absorption peak mainly reflects the residual of SiOH group, and the residual of active SiOH group would cause problems in shelf stability when applied in liquid silicone rubber and other products.

(17) Within this M/Q ratio range, the MQ resin prepared with the present application method, has nearly none residual of SiOH group, but the MQ resin prepared with the traditional method dose have a small residue of SiOH group, which illustrates the advantage of the present application method compared with the traditional method, on disposing residual of SiOH group.

(18) In summary, compared with the prior art, the present application has great advantages, namely, solvent-free and environmental-friendly, one-step reaction and efficient process, high yield of MQ resin, low volatile content, having excellent performance in wide applications.

(19) The embodiment of the present application described above is just a preferred embodiment, it is not just limited to the above embodiment, any other change, like modifications, substitutions, combinations, simplification, made in the present application does not depart from the spirit and principles, shall be equivalent replacement and included within the scope of the present application.