CN115536824A - Preparation method of low-cyclic by-product poly (butylene succinate) polyester - Google Patents
Preparation method of low-cyclic by-product poly (butylene succinate) polyester Download PDFInfo
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- CN115536824A CN115536824A CN202211196058.9A CN202211196058A CN115536824A CN 115536824 A CN115536824 A CN 115536824A CN 202211196058 A CN202211196058 A CN 202211196058A CN 115536824 A CN115536824 A CN 115536824A
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- magnesium
- titanium
- ionic liquid
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- butylene succinate
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- 239000006227 byproduct Substances 0.000 title claims abstract description 37
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- ZMKVBUOZONDYBW-UHFFFAOYSA-N 1,6-dioxecane-2,5-dione Chemical compound O=C1CCC(=O)OCCCCO1 ZMKVBUOZONDYBW-UHFFFAOYSA-N 0.000 title claims abstract description 14
- 229920000728 polyester Polymers 0.000 title description 25
- 239000003054 catalyst Substances 0.000 claims abstract description 33
- 125000004122 cyclic group Chemical group 0.000 claims abstract description 29
- 238000000034 method Methods 0.000 claims abstract description 28
- 238000006243 chemical reaction Methods 0.000 claims abstract description 25
- KDYFGRWQOYBRFD-UHFFFAOYSA-N Succinic acid Natural products OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000002608 ionic liquid Substances 0.000 claims abstract description 23
- PFTAWBLQPZVEMU-DZGCQCFKSA-N (+)-catechin Chemical compound C1([C@H]2OC3=CC(O)=CC(O)=C3C[C@@H]2O)=CC=C(O)C(O)=C1 PFTAWBLQPZVEMU-DZGCQCFKSA-N 0.000 claims abstract description 16
- ADRVNXBAWSRFAJ-UHFFFAOYSA-N catechin Natural products OC1Cc2cc(O)cc(O)c2OC1c3ccc(O)c(O)c3 ADRVNXBAWSRFAJ-UHFFFAOYSA-N 0.000 claims abstract description 16
- 235000005487 catechin Nutrition 0.000 claims abstract description 16
- 229950001002 cianidanol Drugs 0.000 claims abstract description 16
- WERYXYBDKMZEQL-UHFFFAOYSA-N butane-1,4-diol Chemical compound OCCCCO WERYXYBDKMZEQL-UHFFFAOYSA-N 0.000 claims abstract description 13
- 238000005886 esterification reaction Methods 0.000 claims abstract description 12
- 238000006068 polycondensation reaction Methods 0.000 claims abstract description 12
- 229920000642 polymer Polymers 0.000 claims abstract description 12
- SXSVTGQIXJXKJR-UHFFFAOYSA-N [Mg].[Ti] Chemical compound [Mg].[Ti] SXSVTGQIXJXKJR-UHFFFAOYSA-N 0.000 claims abstract description 10
- KDYFGRWQOYBRFD-NUQCWPJISA-N butanedioic acid Chemical compound O[14C](=O)CC[14C](O)=O KDYFGRWQOYBRFD-NUQCWPJISA-N 0.000 claims abstract description 8
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 43
- 238000005470 impregnation Methods 0.000 claims description 23
- 238000001035 drying Methods 0.000 claims description 19
- 239000002904 solvent Substances 0.000 claims description 16
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims description 14
- 239000007788 liquid Substances 0.000 claims description 14
- -1 SS1 titanium compound Chemical class 0.000 claims description 13
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 13
- 239000007787 solid Substances 0.000 claims description 13
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 12
- 239000002808 molecular sieve Substances 0.000 claims description 12
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims description 12
- 239000010936 titanium Substances 0.000 claims description 11
- 238000009210 therapy by ultrasound Methods 0.000 claims description 9
- 229910052719 titanium Inorganic materials 0.000 claims description 9
- 229920002961 polybutylene succinate Polymers 0.000 claims description 8
- 239000004631 polybutylene succinate Substances 0.000 claims description 8
- 239000001384 succinic acid Substances 0.000 claims description 8
- VXUYXOFXAQZZMF-UHFFFAOYSA-N titanium(IV) isopropoxide Chemical compound CC(C)O[Ti](OC(C)C)(OC(C)C)OC(C)C VXUYXOFXAQZZMF-UHFFFAOYSA-N 0.000 claims description 8
- YHWCPXVTRSHPNY-UHFFFAOYSA-N butan-1-olate;titanium(4+) Chemical compound [Ti+4].CCCC[O-].CCCC[O-].CCCC[O-].CCCC[O-] YHWCPXVTRSHPNY-UHFFFAOYSA-N 0.000 claims description 7
- 229910001629 magnesium chloride Inorganic materials 0.000 claims description 7
- 150000002576 ketones Chemical class 0.000 claims description 6
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 5
- 229910052749 magnesium Inorganic materials 0.000 claims description 5
- 239000011777 magnesium Substances 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 4
- 150000002681 magnesium compounds Chemical class 0.000 claims description 4
- 159000000003 magnesium salts Chemical class 0.000 claims description 4
- JMXKSZRRTHPKDL-UHFFFAOYSA-N titanium ethoxide Chemical compound [Ti+4].CC[O-].CC[O-].CC[O-].CC[O-] JMXKSZRRTHPKDL-UHFFFAOYSA-N 0.000 claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- 125000002883 imidazolyl group Chemical group 0.000 claims description 3
- 150000003609 titanium compounds Chemical class 0.000 claims description 3
- IAZSXUOKBPGUMV-UHFFFAOYSA-N 1-butyl-3-methyl-1,2-dihydroimidazol-1-ium;chloride Chemical compound [Cl-].CCCC[NH+]1CN(C)C=C1 IAZSXUOKBPGUMV-UHFFFAOYSA-N 0.000 claims description 2
- GPUZITRZAZLGKZ-UHFFFAOYSA-N 1-hexyl-3-methyl-1,2-dihydroimidazol-1-ium;chloride Chemical compound [Cl-].CCCCCC[NH+]1CN(C)C=C1 GPUZITRZAZLGKZ-UHFFFAOYSA-N 0.000 claims description 2
- 125000000217 alkyl group Chemical group 0.000 claims description 2
- 125000004432 carbon atom Chemical group C* 0.000 claims description 2
- GUJOJGAPFQRJSV-UHFFFAOYSA-N dialuminum;dioxosilane;oxygen(2-);hydrate Chemical compound O.[O-2].[O-2].[O-2].[Al+3].[Al+3].O=[Si]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O GUJOJGAPFQRJSV-UHFFFAOYSA-N 0.000 claims description 2
- ITNVWQNWHXEMNS-UHFFFAOYSA-N methanolate;titanium(4+) Chemical compound [Ti+4].[O-]C.[O-]C.[O-]C.[O-]C ITNVWQNWHXEMNS-UHFFFAOYSA-N 0.000 claims description 2
- 229910052901 montmorillonite Inorganic materials 0.000 claims description 2
- 238000002791 soaking Methods 0.000 claims description 2
- 150000004715 keto acids Chemical class 0.000 claims 1
- 238000010438 heat treatment Methods 0.000 description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 18
- 239000003153 chemical reaction reagent Substances 0.000 description 16
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 12
- 239000000047 product Substances 0.000 description 9
- 230000000052 comparative effect Effects 0.000 description 8
- 230000032050 esterification Effects 0.000 description 7
- CDQSJQSWAWPGKG-UHFFFAOYSA-N butane-1,1-diol Chemical compound CCCC(O)O CDQSJQSWAWPGKG-UHFFFAOYSA-N 0.000 description 6
- 238000001816 cooling Methods 0.000 description 6
- 238000005453 pelletization Methods 0.000 description 6
- 238000003756 stirring Methods 0.000 description 6
- 238000005303 weighing Methods 0.000 description 6
- 230000015556 catabolic process Effects 0.000 description 4
- 230000003197 catalytic effect Effects 0.000 description 4
- 238000006731 degradation reaction Methods 0.000 description 4
- 125000004185 ester group Chemical group 0.000 description 4
- 238000002803 maceration Methods 0.000 description 4
- 229920002521 macromolecule Polymers 0.000 description 4
- NKRASMXHSQKLHA-UHFFFAOYSA-M 1-hexyl-3-methylimidazolium chloride Chemical compound [Cl-].CCCCCCN1C=C[N+](C)=C1 NKRASMXHSQKLHA-UHFFFAOYSA-M 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000005336 cracking Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- FHDQNOXQSTVAIC-UHFFFAOYSA-M 1-butyl-3-methylimidazol-3-ium;chloride Chemical compound [Cl-].CCCCN1C=C[N+](C)=C1 FHDQNOXQSTVAIC-UHFFFAOYSA-M 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 235000013361 beverage Nutrition 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000005227 gel permeation chromatography Methods 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000007363 ring formation reaction Methods 0.000 description 2
- 238000007086 side reaction Methods 0.000 description 2
- 230000002195 synergetic effect Effects 0.000 description 2
- 238000002604 ultrasonography Methods 0.000 description 2
- BYEAHWXPCBROCE-UHFFFAOYSA-N 1,1,1,3,3,3-hexafluoropropan-2-ol Chemical compound FC(F)(F)C(O)C(F)(F)F BYEAHWXPCBROCE-UHFFFAOYSA-N 0.000 description 1
- 239000005909 Kieselgur Substances 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- FAWGZAFXDJGWBB-UHFFFAOYSA-N antimony(3+) Chemical compound [Sb+3] FAWGZAFXDJGWBB-UHFFFAOYSA-N 0.000 description 1
- 239000004621 biodegradable polymer Substances 0.000 description 1
- 229920002988 biodegradable polymer Polymers 0.000 description 1
- 239000006085 branching agent Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002290 gas chromatography-mass spectrometry Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 239000005022 packaging material Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 239000010902 straw Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000013638 trimer Substances 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
- 230000002087 whitening effect Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/78—Preparation processes
- C08G63/82—Preparation processes characterised by the catalyst used
- C08G63/87—Non-metals or inter-compounds thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
- C08G63/12—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from polycarboxylic acids and polyhydroxy compounds
- C08G63/16—Dicarboxylic acids and dihydroxy compounds
- C08G63/20—Polyesters having been prepared in the presence of compounds having one reactive group or more than two reactive groups
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/66—Polyesters containing oxygen in the form of ether groups
- C08G63/668—Polyesters containing oxygen in the form of ether groups derived from polycarboxylic acids and polyhydroxy compounds
- C08G63/672—Dicarboxylic acids and dihydroxy compounds
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/78—Preparation processes
- C08G63/82—Preparation processes characterised by the catalyst used
- C08G63/83—Alkali metals, alkaline earth metals, beryllium, magnesium, copper, silver, gold, zinc, cadmium, mercury, manganese, or compounds thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/78—Preparation processes
- C08G63/82—Preparation processes characterised by the catalyst used
- C08G63/85—Germanium, tin, lead, arsenic, antimony, bismuth, titanium, zirconium, hafnium, vanadium, niobium, tantalum, or compounds thereof
Abstract
The invention provides a preparation method of poly (butylene succinate) (PBS) with low cyclic by-products. The method comprises the following steps: adding succinic acid, 1,4-butanediol and catechin into a reaction kettle for esterification reaction; adding a titanium-magnesium bimetal supported ionic liquid catalyst into the reaction kettle to carry out polycondensation reaction to obtain a polymer melt, and granulating to obtain the poly (butylene succinate) polymer. The content of the PBS cyclic byproduct is less than or equal to 1wt%, and the PBS cyclic byproduct has excellent mechanical properties.
Description
Technical Field
The invention belongs to the field of biodegradable polymer materials, and particularly relates to a preparation method of a low-cyclic by-product poly (butylene succinate).
Background
Polyesters represented by polybutylene succinate (PBS) and mainly synthesized from aliphatic diols and aliphatic dicarboxylic acids are milky in appearance, have good impact strength and biodegradability, and are mainly used in the field of food contact materials such as straws, packaging materials, beverage bottles, and the like. However, the above-mentioned products have problems such as whitening and loss of gloss on the surface after they are left for a certain period of time, and it has been studied that the cyclic by-products contained in the polyester are precipitated, and if the cyclic by-products are too large, the by-products are also transferred to the content liquid when the polyester is used for preparing beverage bottles, which affects the popularization and application of the polyester. The cyclic byproducts in PET are currently studied more and PBS is less.
The existing methods for reducing cyclic byproducts in polyester mainly comprise two types, one is to prepare the polyester and then carry out post-treatment on the polyester, for example, EP-A2623540, japanese patent application laid-open No. 2004-107457, and Japanese patent application laid-open No. 7-316276 all disclose a method for reducing cyclic byproducts by treating PBS polyester with solvent, but the method has the defects of polyester degradation, uncontrollable molecular weight, poor mechanical properties and solvent residue influencing the polyester application. Another method is to reduce the production of cyclic by-products during the polyester synthesis, and Japanese patent No. 12-219731 discloses the addition of S0 in the polycondensation stage 3 The sulfite compound of X can effectively reduce the cyclic by-products in the PET polyester, and Japanese patent 12-219729 discloses a method for effectively controlling the content of the cyclic by-products in the PET by controlling the molar ratio of antimony element to phosphoric acid, but the research on the lower cyclic by-products in the PBS polyester synthesis process is less.
In conclusion, a method for preparing poly (butylene succinate) with low cyclic by-products by an efficient and easily-realized industrialization method is urgently needed.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides the preparation method of the polybutylene succinate-butanediol Polyester (PBS), the method can effectively reduce the generation of cyclic byproducts in the synthesis process, the obtained PBS can be directly used for food contact materials, and the PBS post-treatment step is omitted.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of low cyclic by-product poly (butylene succinate) (PBS), comprising the following steps:
s1: adding succinic acid, 1,4-butanediol and catechin into a reaction kettle for esterification reaction;
s2: adding a titanium-magnesium bimetal supported ionic liquid catalyst into the reaction kettle to carry out polycondensation reaction to obtain a polymer melt, and granulating to obtain the poly (butylene succinate) polymer.
In the field of PBS preparation, polyester obtained by the reaction of dibasic acid and dihydric alcohol inevitably generates cyclic byproducts, and researches suggest that the cyclic byproducts can be the interchange of ester groups between adjacent macromolecules, or the inner cyclization of macromolecules, or the end group cyclization of macromolecules, or carboxyl groups formed in thermal degradation to generate cyclic oligomers, or the closed-loop condensation of monomer oligomers, wherein the possibility of the chain ends of the macromolecules to form the cyclic oligomers by attacking the cracking of the ester groups is the greatest, and the following formula is the generation process of one cyclic trimer:
different from the traditional titanate catalyst, the titanium-magnesium bimetal load type ionic liquid catalyst changes the electron distribution around the titanium of the catalytic active center through the synergistic effect of the bimetal and the ionic liquid, and generates a stabilizing effect on polyester, so that the generation of cyclic byproducts can be inhibited under high-temperature melting, the hydrolysis resistance of the catalyst is improved, and the catalyst can be stored for a long time.
In the invention, catechin is introduced, and the introduction of large pi bonds changes the electron cloud distribution of macromolecular chains, inhibits the chain-end hydroxyl from attacking ester group and cracking to form rings, thereby effectively reducing the generation of cyclic byproducts. Meanwhile, catechin is combined with the ionic liquid with an imidazole structure in a pi-pi interaction mode, so that the catalytic effect of a catalytic activity center on side reactions such as thermal degradation and the like is effectively reduced.
In the present invention, the amount of catechin used in S1 is 0.05 to 5%, preferably 0.5 to 1%, based on the mass of succinic acid.
In the present invention, the molar ratio of the succinic acid to 1,4-butanediol in S1 is 1.1 to 1.5, preferably 1.
In the invention, the esterification reaction temperature of S1 is 180-250 ℃.
In the invention, the addition amount of the titanium-magnesium bimetal supported ionic liquid catalyst S2 is 0.01-1%, preferably 0.1-0.5% of the mass of the succinic acid.
In the invention, the polycondensation reaction of S2 is vacuumized twice, the first time is vacuumized to 1000-30,000PaA, and the time lasts for 10-60 min; vacuumizing for the second time to less than 100PaA, and reacting at 220-270 deg.c for 60-200 min. The double vacuum process is a common process for preparing PBS, and other non-preferred schemes besides the above process can be adopted in the invention.
The invention also aims to provide a preparation method of the titanium-magnesium bimetal supported ionic liquid catalyst.
A preparation method of a titanium-magnesium bimetal supported ionic liquid catalyst comprises the following steps:
and (4) SS1: dissolving a titanium compound in a solvent to obtain a titanium impregnation solution;
and SS2: dissolving a magnesium compound in a solvent to obtain a magnesium impregnation solution;
and (4) SS3: mixing soaking solutions prepared from SS1 and SS2, adding a carrier, performing ultrasonic treatment, and drying;
and SS4: dissolving the solid obtained by SS3 in a solvent, adding ionic liquid, performing ultrasonic treatment, and drying.
In the invention, the titanium compound in SS1 is titanate Ti (OR) 4 R is an alkyl group of 1 to 10 carbon atoms, preferably one or more of tetrabutyl titanate, tetraisopropyl titanate, tetraethyl titanate and tetramethyl titanate.
In the invention, the solvent of SS1 is one or more of alcohol, ketone and ether, preferably C2-C4 small molecular alcohol, and more preferably ethanol; preferably, the titanium impregnation solution of SS1 has a solubility of 0.01 to 10mmol/mL, preferably 0.1 to 1mmol/mL.
In the present invention, the magnesium compound described in SS2 is a magnesium salt, preferably a magnesium salt of an oxygen-free acid, and more preferably magnesium chloride.
In the invention, the solvent of SS2 is one or more of alcohol, ketone and ether, preferably C2-C4 small molecular alcohol, and more preferably ethanol.
In the present invention, the magnesium-impregnated solution described in SS2 has a solubility of 0.01 to 10mmol/mL, preferably 0.1 to 1mmol/mL.
In the present invention, the molar ratio of the elements of titanium to magnesium in the mixed impregnation solution of SS3 is 1 to 7:1, preferably 2 to 4:1.
in the invention, the carrier SS3 is one or more of molecular sieve, active carbon, diatomite and montmorillonite, preferably molecular sieve, more preferably 50-200 mesh molecular sieve; preferably, the ratio of the mass of the added carrier of SS3 to the volume of the mixed impregnation solution is 1/20-1/4 g/mL, preferably 1/10-1/5 g/mL.
In the invention, the ultrasonic temperature of SS3 is 20-60 ℃, preferably 30-50 ℃; the ultrasonic time is 3 to 10 hours, preferably 4 to 6 hours; the drying temperature is 80-150 ℃, preferably 100-120 ℃, and the drying time is 5-48 h, preferably 12-24 h.
In the present invention, the amount of the solvent described in SS4 is 3 to 10 times, preferably 5 to 7 times, the mass of the solid obtained from SS 3.
In the invention, the solvent of SS4 is one or more of alcohol, ketone and ether, preferably C2-C4 small molecular alcohol, and more preferably ethanol.
In the invention, the ionic liquid SS4 is an ionic liquid containing an imidazole structure, preferably 1-butyl-3-methylimidazole chloride salt and/or 1-hexyl-3-methylimidazole chloride salt; preferably, the ionic liquid is used in an amount of 1 to 5 times, preferably 2 to 4 times, the mass of the solid obtained from SS 3.
In the invention, the ultrasonic temperature of SS4 is 20-60 ℃, preferably 30-50 ℃; the ultrasonic time is 3 to 10 hours, preferably 4 to 6 hours; the drying temperature is 100-300 ℃, preferably 150-200 ℃, and the drying time is 5-48 h, preferably 12-24 h.
The invention also aims to provide a polybutylene succinate product.
A Poly Butylene Succinate (PBS) is prepared by the preparation method or is prepared by the catalyst prepared by the method, the content of poly butylene succinate cyclic by-products in the poly butylene succinate is less than or equal to 1wt%, preferably less than or equal to 0.5wt%, based on the total mass of the poly butylene succinate; wherein the poly butylene succinate cyclic byproduct has the following structure:
wherein n is a positive integer less than 10.
Compared with the prior art, the technical scheme of the invention has the advantages that:
(1) Catechin is added in the esterification stage to play a role of a branching agent, so that PBS with lower melt index can be prepared, meanwhile, the introduction of a large pi bond changes the electron cloud distribution of a macromolecular chain, and inhibits the chain-end hydroxyl from attacking ester group and cracking to form ring, thereby effectively reducing the generation of cyclic byproducts;
(2) Through the synergistic effect of the bimetal, the ionic liquid and the catechin, on one hand, the activity of titanium is effectively regulated and controlled, the catalytic action of the titanium on side reactions such as thermal degradation is reduced, on the other hand, the generation of annular byproducts is also effectively reduced, and the catalyst has better hydrolysis resistance, so that the utilization rate of the catalyst is greatly improved.
Detailed Description
The present invention is further illustrated by the following examples, which should be construed as limiting the scope of the invention.
Raw materials:
succinic acid, superior products, shandong Feiyang chemical Co., ltd;
1,4-Butanediol (BDO), technical grade, mazej chemical ltd;
catechin 97%, reagent grade, alatin reagent ltd;
98% tetraisopropyl titanate, reagent grade, alatin reagent ltd;
98% tetrabutyl titanate, reagent grade, alatin reagent ltd;
99% magnesium chloride, reagent grade, aladine reagent ltd;
diatomaceous earth, median particle size 19.6 microns, alatin reagent ltd;
4A molecular sieve, 200 mesh, allatin reagents, inc.;
4A molecular sieve, 100 mesh, allatin reagents, inc.;
4A molecular sieve, 50 mesh, alatin reagent ltd;
98% of 1-butyl-3-methylimidazolium chloride, analytically pure, alatin reagent ltd;
98% of 1-hexyl-3-methylimidazolium chloride salt, analytically pure, alatin reagent, ltd;
methanol, analytical grade, alatin reagent ltd;
ethanol, analytical grade, alatin reagent ltd;
the apparatus and methods used in the present invention are those commonly used in the art, except where specifically indicated. Wherein the molecular weight of the sample was measured by using a Gel Permeation Chromatography (GPC) instrument model 1515-2414 from Waters, USA, wherein hexafluoroisopropanol is used as a mobile phase, the outflow rate is 1ml/min, the column temperature is 30 ℃, and the standard sample is polystyrene.
The mechanical properties were tested by the following methods: tensile properties were measured using a mechanical tester (Instron 5960) at a tensile rate of 50mm/min.
The cyclic by-products were characterized by semer fly TSQ 8000Evo gas chromatography-mass spectrometry (GC-MS).
Catalyst preparation
Example 1
Weighing 10mmol of tetraisopropyl titanate to dissolve in 1000mL of methanol to obtain SS1 maceration extract, weighing 10mmol of magnesium chloride to dissolve in 1000mL of methanol to obtain SS2 maceration extract, mixing 100mL of SS1 maceration extract with 100mL of SS2 maceration extract, adding 50g of diatomite, performing ultrasonic treatment at 20 ℃ for 3 hours, drying at 80 ℃ for 5 hours to obtain SS3 solid, dissolving 10g of SS3 solid in 30g of methanol, adding 10g of 1-butyl-3-methylimidazolium chloride, performing ultrasonic treatment at 20 ℃ for 3 hours, and drying at 100 ℃ for 5 hours to obtain catalyst A.
Example 2
10000mmol of tetrabutyl titanate is weighed and dissolved in 1000mL of ethanol to obtain SS1 impregnation liquid, 10000mmol of magnesium chloride is weighed and dissolved in 1000mL of ethanol to obtain SS2 impregnation liquid, 700mL of the SS1 impregnation liquid and 100mL of the SS2 impregnation liquid are mixed, 40g of a 50-mesh 4A molecular sieve is added, 300W ultrasound is carried out for 10 hours at the temperature of 60 ℃, drying is carried out for 48 hours at the temperature of 150 ℃ to obtain SS3 solid, 10g of the SS3 solid is dissolved in 100g of ethanol, 50g of 1-hexyl-3-methylimidazolium chloride is added, ultrasound is carried out for 10 hours at the temperature of 60 ℃, and drying is carried out for 48 hours at the temperature of 300 ℃ to obtain a catalyst B.
Example 3
Weighing 500mmol of tetrabutyl titanate to dissolve in 1000mL of ethanol to obtain SS1 impregnation liquid, weighing 500mmol of magnesium chloride to dissolve in 1000mL of ethanol to obtain SS2 impregnation liquid, mixing 300mL of SS1 impregnation liquid with 100mL of SS2 impregnation liquid, adding a 60g 200-mesh 4A molecular sieve, carrying out ultrasonic treatment at 40 ℃ for 5 hours, drying at 110 ℃ for 20 hours to obtain SS3 solid, dissolving 10g of SS3 solid in 60g of ethanol, adding 30g of 1-hexyl-3-methylimidazolium chloride, carrying out ultrasonic treatment at 40 ℃ for 5 hours, and drying at 180 ℃ for 20 hours to obtain catalyst C.
Comparative example 1
In contrast to example 3, no ionic liquid was added to the catalyst preparation in this comparative example.
Weighing 500mmol of tetrabutyl titanate to dissolve in 1000mL of ethanol to obtain SS1 impregnation liquid, weighing 500mmol of magnesium chloride to dissolve in 1000mL of ethanol to obtain SS2 impregnation liquid, mixing 300mL of SS1 impregnation liquid and 100mL of SS2 impregnation liquid, adding 60g of 100-mesh 4A molecular sieve, carrying out ultrasonic treatment at 300W at 40 ℃ for 5 hours, and drying at 110 ℃ for 20 hours to obtain SS3 solid, thus obtaining the catalyst D.
Preparing polyester:
example 4
Adding 10mol of succinic acid, 15mol of butanediol and 59g of catechin into a 5L polyester kettle, keeping the normal pressure in the kettle, stirring at a constant speed of 100rpm, heating to 150 ℃, starting the reaction, gradually heating to 180 ℃ within 1 hour, and finishing the esterification process when the amount of distilled by-product water in the reaction kettle reaches 95% of theoretical water yield. Adding 11.8g of catalyst A, gradually vacuumizing the reaction kettle to 30,000PaA for 60min, then gradually vacuumizing to 60PaA, heating to 220 ℃ and keeping, carrying out polycondensation reaction for 200min to obtain a polymer melt, and carrying out water cooling and pelletizing to obtain the product.
Example 5
Adding 10mol of succinic acid, 11mol of butanediol and 0.59g of catechin into a 5L polyester kettle, keeping normal pressure in the kettle, stirring at a constant speed of 100rpm, heating to 150 ℃, starting reaction, gradually heating to 250 ℃ within 1h, and finishing the esterification process when the amount of distilled by-product water in the reaction kettle reaches 95% of theoretical water yield. Adding 0.118g of catalyst B, gradually vacuumizing the reaction kettle to 1,000PaA for 20min, then gradually vacuumizing to 60PaA, heating to 270 ℃ and keeping, carrying out polycondensation reaction for 100min to obtain a polymer melt, and carrying out water cooling and pelletizing to obtain the product.
Example 6
Adding 10mol of succinic acid, 12mol of butanediol and 9.44g of catechin into a 5L polyester kettle, keeping normal pressure in the kettle, stirring at a constant speed of 100rpm, heating to 150 ℃, starting reaction, gradually heating to 230 ℃ within 1h, and finishing the esterification process when the amount of distilled by-product water in the reaction kettle reaches 95% of theoretical water yield. Adding 3.54g of catalyst C, gradually vacuumizing the reaction kettle to 3,000PaA for 50min, then gradually vacuumizing to 60PaA, heating to 250 ℃ and keeping, carrying out polycondensation reaction for 150min to obtain a polymer melt, and carrying out water cooling and pelletizing to obtain the product.
Comparative example 2
In comparison with example 6, no catechin was added in this comparative example.
Adding 10mol of succinic acid and 12mol of butanediol into a 5L polyester kettle, keeping normal pressure in the kettle, stirring at a constant speed of 100rpm, heating to 150 ℃, starting reaction, gradually heating to 230 ℃ within 1h, and finishing the esterification process when the amount of by-product water distilled out of the reaction kettle reaches 95% of theoretical water yield. Adding 3.54g of catalyst C, gradually vacuumizing the reaction kettle to 3,000PaA for 50min, then gradually vacuumizing to 60PaA, heating to 250 ℃ and keeping, carrying out polycondensation reaction for 150min to obtain a polymer melt, and carrying out water cooling and pelletizing to obtain the product.
Comparative example 3
In contrast to example 6, this comparative example used a catalyst without the addition of an ionic liquid.
Adding 10mol of succinic acid, 12mol of butanediol and 9.44g of catechin into a 5L polyester kettle, keeping normal pressure in the kettle, stirring at a constant speed of 100rpm, heating to 150 ℃, starting reaction, gradually heating to 230 ℃ within 1h, and finishing the esterification process when the amount of distilled by-product water in the reaction kettle reaches 95% of theoretical water yield. Adding 3.54g of catalyst D, gradually vacuumizing the reaction kettle to 3,000PaA for 50min, then gradually vacuumizing to 60PaA, heating to 250 ℃ and keeping, carrying out polycondensation reaction for 150min to obtain a polymer melt, and carrying out water cooling and pelletizing to obtain the product.
Comparative example 4
In contrast to example 6, this comparative example did not add catechin and the titanate was added directly as a catalyst.
Adding 10mol of succinic acid and 12mol of butanediol into a 5L polyester kettle, keeping normal pressure in the kettle, stirring at a constant speed of 100rpm, heating to 150 ℃, starting reaction, gradually heating to 230 ℃ within 1h, and finishing the esterification process when the amount of by-product water distilled out of the reaction kettle reaches 95% of theoretical water yield. Adding 3.54g of tetrabutyl titanate, gradually vacuumizing the reaction kettle to 3,000PaA for 50min, then gradually vacuumizing to 60PaA, heating to 250 ℃ and keeping, carrying out polycondensation reaction for 150min to obtain a polymer melt, and carrying out water cooling and pelletizing to obtain the product.
TABLE 1 PBS Properties
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.
Claims (9)
1. A preparation method of low cyclic by-product poly (butylene succinate) is characterized by comprising the following steps:
s1: adding succinic acid, 1,4-butanediol and catechin into a reaction kettle for esterification reaction;
s2: and adding a titanium-magnesium bimetal supported ionic liquid catalyst into the reaction kettle to perform polycondensation reaction to obtain a polymer melt, and granulating to obtain the poly (butylene succinate) polymer.
2. The preparation method according to claim 1, characterized in that the catechin of S1 is added in an amount of 0.05-5%, preferably 0.5-1% of the mass of succinic acid;
and/or the molar ratio of the succinic acid and 1,4-butanediol in S1 is 1.1-1, preferably 1.1-1;
and/or the esterification reaction temperature of S1 is 180-250 ℃.
3. The preparation method according to claim 1, wherein the titanium-magnesium bimetal supported ionic liquid catalyst S2 is added in an amount of 0.01-1%, preferably 0.1-0.5% of the mass of the succinic acid;
and/or, the polycondensation reaction of S2 is vacuumized twice, the first time is vacuumized to 1000-30,000PaA, and the time lasts for 10-60 min; vacuumizing for the second time to less than 100PaA, and reacting at 220-270 deg.c for 60-200 min.
4. A method for preparing a titanium-magnesium bimetal supported ionic liquid catalyst, which is the titanium-magnesium bimetal supported ionic liquid catalyst in any one of claims 1 to 3, and is characterized by comprising the following steps:
SS1: dissolving a titanium compound in a solvent to obtain a titanium impregnation solution;
and (4) SS2: dissolving a magnesium compound in a solvent to obtain a magnesium impregnation solution;
and (4) SS3: mixing soaking solutions prepared from SS1 and SS2, adding a carrier, performing ultrasonic treatment, and drying;
and SS4: dissolving the solid obtained by SS3 in a solvent, adding ionic liquid, performing ultrasonic treatment, and drying.
5. According to claim 4The preparation method of the catalyst is characterized in that SS1 titanium compound is titanate Ti (OR) 4 R is alkyl of 1 to 10 carbon atoms, preferably one or more of tetrabutyl titanate, tetraisopropyl titanate, tetraethyl titanate and tetramethyl titanate;
and/or the solvent of SS1 is one or more of alcohol, ketone and ether, preferably C2-C4 small molecular alcohol, more preferably ethanol;
preferably, the titanium impregnation solution of SS1 has a solubility of 0.01 to 10mmol/mL, preferably 0.1 to 1mmol/mL.
6. The method for preparing a catalyst according to claim 4, wherein the magnesium compound of SS2 is a magnesium salt, preferably a magnesium salt of an oxoacid, more preferably magnesium chloride;
and/or the solvent of SS2 is one or more of alcohol, ketone and ether, preferably C2-C4 small molecular alcohol, more preferably ethanol;
and/or the solubility of the magnesium impregnation solution in SS2 is 0.01-10 mmol/mL, preferably 0.1-1 mmol/mL.
7. The method according to claim 4, wherein the molar ratio of the elements of titanium to magnesium in the mixed impregnation solution of SS3 is 1 to 7:1, preferably 2 to 4:1;
and/or the SS3 carrier is one or more of molecular sieve, activated carbon, diatomite and montmorillonite, preferably the molecular sieve, more preferably the molecular sieve with 50-200 meshes;
preferably, the ratio of the mass of the added carrier of SS3 to the volume of the mixed impregnation liquid is 1/20-1/4 g/mL, preferably 1/10-1/5 g/mL;
and/or the ultrasonic temperature of SS3 is 20-60 ℃, preferably 30-50 ℃; the ultrasonic time is 3 to 10 hours, preferably 4 to 6 hours; the drying temperature is 80-150 ℃, preferably 100-120 ℃, and the drying time is 5-48 h, preferably 12-24 h.
8. The process for the preparation of the catalyst according to claim 4, characterized in that the solvent of SS4 is used in an amount of 3 to 10 times, preferably 5 to 7 times, the mass of the solid obtained from SS 3;
and/or the solvent of SS4 is one or more of alcohol, ketone and ether, preferably C2-C4 small molecular alcohol, more preferably ethanol;
and/or the ionic liquid SS4 is an ionic liquid containing an imidazole structure, preferably 1-butyl-3-methylimidazole chloride salt and/or 1-hexyl-3-methylimidazole chloride salt;
preferably, the amount of ionic liquid used is 1 to 5 times, preferably 2 to 4 times, the mass of the solid obtained from SS 3;
and/or the ultrasonic temperature of SS4 is 20-60 ℃, preferably 30-50 ℃; the ultrasonic time is 3 to 10 hours, preferably 4 to 6 hours; the drying temperature is 100-300 ℃, preferably 150-200 ℃, and the drying time is 5-48 h, preferably 12-24 h.
9. A poly (butylene succinate) prepared by the preparation method of any one of claims 1 to 3 or catalyzed by the catalyst prepared by the method of any one of claims 4 to 8, wherein the content of cyclic side products of the poly (butylene succinate) in the poly (butylene succinate) is less than or equal to 1wt%, preferably less than or equal to 0.5wt%, based on the total mass of the poly (butylene succinate);
wherein the poly butylene succinate cyclic byproduct has the following structure:
wherein n is a positive integer less than 10.
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