WO2012114357A1 - Process for preparing hyperbranched polyestersfield of the invention - Google Patents

Process for preparing hyperbranched polyestersfield of the invention Download PDF

Info

Publication number
WO2012114357A1
WO2012114357A1 PCT/IN2012/000125 IN2012000125W WO2012114357A1 WO 2012114357 A1 WO2012114357 A1 WO 2012114357A1 IN 2012000125 W IN2012000125 W IN 2012000125W WO 2012114357 A1 WO2012114357 A1 WO 2012114357A1
Authority
WO
WIPO (PCT)
Prior art keywords
catalyst
range
acid
reaction
double
Prior art date
Application number
PCT/IN2012/000125
Other languages
French (fr)
Other versions
WO2012114357A8 (en
Inventor
Darbha SRINAVAS
Joby SEBASTIAN
Original Assignee
Council Of Scientific & Industrial Research
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Council Of Scientific & Industrial Research filed Critical Council Of Scientific & Industrial Research
Priority to EP12715442.5A priority Critical patent/EP2678370B1/en
Priority to US14/001,322 priority patent/US9334361B2/en
Priority to BR112013021671A priority patent/BR112013021671A2/en
Priority to CN201280018710.6A priority patent/CN103476824B/en
Priority to RU2013142982/04A priority patent/RU2596831C2/en
Publication of WO2012114357A1 publication Critical patent/WO2012114357A1/en
Publication of WO2012114357A8 publication Critical patent/WO2012114357A8/en

Links

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
    • C08G63/83—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
    • C08G63/02—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
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/24—Nitrogen compounds
    • B01J27/26—Cyanides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/64—Pore diameter
    • B01J35/647—2-50 nm
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Definitions

  • the present invention relates to a process for preparing hyperbranched polyesters in the presence of a solid-acid catalyst.
  • the present invention relates to an efficient, eco-friendly, solvent-free process for preparing hyperbranched polyesters comprising contacting polyols with polycarboxylic acids in the presence of a solid, acidic, crystalline, micro-mesoporous double- metal cyanide catalyst.
  • Hyperbranched polyesters belong to the family of dendrimers bearing large number of functional groups on their periphery. Despite their high polydispersities and low degree of branching, their chemical performances are quite similar to their dendrimer analogues. Topological specifics of hyperbranched polymers like high level of solubility and compatibility, low viscosity of solutions, resistance to aggregate even in concentrated solutions, ability to function as nanocontainers for substances sorbed inside, weak dependence of hydrodynamic volume on molecular weight and lump of free ends of chains with functional groups on their periphery open a new window for their diverse industrial use.
  • Hyperbranched polymers find wide applicability as cosmetics, food additives, surfactants, lubricants, plasticizers, drug delivery agents, azeotropic phase separators, in orthopaedic and ophthalmic fields, building blocks for preparing poly-addition or poly-condensation polymers, additives in paints, coverings, adhesive promoters, sealants, casting elastomers, as rheology modifiers and as surface or interface modifiers.
  • Discovery of unique properties of hyperbranched polyesters has expedited a rapid development in this area of materials. Hyperbranched polyesters derived from renewables broaden their applicability as novel, environmental-friendly materials for various applications.
  • Polyesters are conventionally synthesized by polycondensation of di- or polycarboxylic acids with polyols.
  • aromatic polyesters i.e., polyesters from aromatic dicarboxylic acids such as phthalic acid or terephthalic acid and alcohols such as 1,2-ethane diol, 1,2- or 1,3-propane diol or 1,4-butane diol, are more significant.
  • polyesters derived from parent molecules like succinic acid, glutaric acid or adipic acid and alcohols such as 1,2-ethane diol, 1,2- or 1,3-propane diol, 1,3- or 1,4-butane diol, 1,5-pentane diol or 1,6-hexane diol are making these polymers more attractive in recent years.
  • US 6,441,126 and US 20100048813 describes a process for producing cross-linked, branched, aliphatic polyesters for gum base from glycerol and adipic acid at 150-200°C without any catalyst under solvent-free conditions.
  • EP 0799279 discloses the synthesis from an ethoxylated pentaerythritol and 2,2-dimethylol propanoic acid using conventional homogenous mineral acid catalyst, H 2 S0 4 , at 140°C.
  • H 2 S0 4 homogenous mineral acid catalyst
  • prior arts disclose synthesis of polyesters from different reactants employing different catalysts, in solvent-free conditions or in the presence of solvent.
  • Enzymatic and microbial catalysed processes also form part of prior art in this area. The results of such prior art processes are polyesters that donot possess the characteristics of low viscosity at a high degree of branching and with controlled gelation.
  • a solid catalyst-based process has several engineering, environmental and economic advantages.
  • the solid catalyst can be easily separated and reused in subsequent recycles. It is therefore desirable to develop an efficient solid catalyst-based process for producing hyperbranched polyesters of low-viscosity and high degree of branching with controlled gelation to achieve polyesters for speciality applications.
  • Double-metal cyanides were used as catalysts for the preparation of polyether polyols (WO 2009055436; US 6624286; Chen et al., J Polym Sci A Polym Chem., Year 2004, Vol. 42, pp.6519), alternative copolymerization of epoxides and C0 2 (US Patent Nos. 6,359,101, 6,953,765 and 6,852,663) and biodiesel and biolubricants manufacture by transesterification/esterification of vegetable oils or animal fat (monohydric carboxylic acid) with monohydric alcohols (US Patent Nos. 7,754,643, 7,482,480 and 7,842,653; EP 1 733 788; Sreeprasanth et al., Appl. Catal. A: Gen., Year 2006, Vol. 314, pp. 148).
  • their application for the preparation of hyperbranched polyesters is not disclosed so far.
  • Double metal cyanide catalysts of different crystallite structures (monoclinic) and amorphous nature have been used for the preparation of polyesters and other hybrid polymers as described in the following prior arts.
  • DE 10 2008 004 343 Al discloses a process for preparing polyester alcohol useful to prepare polyurethane foams and thermoplastic polyurethane elastomers, comprising catalytic conversion of at least a difunctional carboxylic acid with at least a difunctional alcohol, where at least a part of the reaction is carried out in the presence of a polymetal cyanide or a double metal cyanide catalyst usually in an amount up to 1% by weight of the reaction mixture.
  • the polycondensation reaction can be performed both in presence and in absence of a solvent at temperature 160 - 280°C. This disclosure is specific for conversion of dicarboxylic compounds with dihydroxy compounds.
  • WO 2011/137011 Al tells a process for preparing a hybrid polyester-polyether polyols comprising reacting a carboxyl group-containing component and an epoxide, optionally in the presence of one or more double metal cyanide catalyst, a superacid catalyst, a metal salt of a superacid catalyst and/or a tertiary amine catalyst, under conditions such that a hybrid polyester-polyether polyol is formed. Further, the said reaction is carried out in presence of solvent such as toluene.
  • the process results in products having narrow polydispersity, a low acid number and unsaturation and reduced byproducts formation, particularly when the metal cyande catalyst is employed.
  • the product is a hybrid polyester-polyether-polyol, different from that of the present invention.
  • US 7842653 describes a process for preparing lubricants wherein the said process comprises contacting a monocarboyxlic vegetable oil or fat with a monohydric C6 - C8 alcohol in the presence of a double-metal cyanide catalyst wherein the vegetable oil/fat to alcohol molar ratio being 1 : 6, reaction temperature being in the range 150 - 200°C and reaction time being in the range 3 - 6 hrs.
  • the product is a monoester.
  • WO 2011/075343 Al discloses a process to convert a secondary hydroxyl-capped polyol to a primary hydroxyl-capped polyol comprises reacting a polyether polyol, a polyester polyol, polyether-ester polyol or a polyether-polyester polyol with a cyclic anhydride of a polycarboxylic acid to form a half acid ester, followed by the reacting the half acid ester with ethylene oxide, to form a polyester polyol or a polyether-polyester polyol. Both steps are carried out in the presence of an amine catalyst and a double metal cyande catalyst.
  • the latter catalyst useful for polymerization of epoxides generally may include an organic complex agent such a diglyme.
  • CN101570595 discloses a terpolymer containing polyester chain links and polycarbonate chain links and a synthetic method thereof, which comprises the mixing of zinc-cobalt double metal cyanide complex catalyst, cyclohexene oxide and dicarboxylic anhydride in a solvent.
  • the double metal cyanide catalyst used in the present invention is unique and thereby shows efficient catalytic activity for the preparation of hyperbranched polyesters.
  • the unusual surface hydrophobicity of the catalyst facilitates the adsorption of polycarboxylic acids and polyols but not the water formed as by-product in the esterification reaction and micro- mesoporous architecture controls the gelation and degree of branching.
  • the main object of present invention is to provide a process for preparing hyperbranched polyesters of low viscosity, high degree of branching and controlled gelation making use of an efficient, reusable, heterogeneous acid catalyst.
  • Another object of present invention is to provide an efficient, eco-friendly process for the synthesis of hyperbranched polyesters from renewables in presence of a solid, reusable, acid catalyst.
  • Yet another objective is to describe a process for providing hyperbranched polyesters at moderate temperatures, short period of reaction time and solvent-free conditions.
  • the present invention provides an efficient, eco-friendly, solvent-free a process for preparing hyper branched polyesters having degree of branching in range 45 - 90% and inherent viscosity in the range 0.02 - 0.1 dL/g and the said process comprising the steps of:
  • step (b) subjecting the reaction mixture as obtained in step (a) at temperature in the range
  • polyesters 160 to 200°C and for a reaction period of 0.5 - 2 h to obtain polyesters;
  • step (c) dissolving the reaction mixture obtained in step (b) in a polar solvent like
  • step (d) adding a non-polar solvent like heptane to the reaction mixture obtained from step (c) to precipitate out and isolate the hyper branched polyesters.
  • step (a) the chemical formula of double metal cyanide Catalyst used in step (a) is :
  • R is tertiary-butyl
  • M is a transition metal ion selected from the group consisting of Fe and Co
  • x varies from 0 to 0.5
  • y varies from 3 - 5
  • n is 10 or 12.
  • the polyol used in step (a) has atlest two alcoholic groups.
  • the polyols is selected from the group consisting of glycerol, sorbitol, mannitol, glucose and sucrose .
  • polycarboxylic acid used in step (a) contains at least two carboxylic groups.
  • polycarboxylic acid used in step (a) is selected from the group consisting of succinic acid and adipic acid.
  • the solid catalyst is reusable.
  • the isolated yield of polyester is in the range 50 - 90 wt%.
  • the double-metal cyanide catalyst was prepared as per the US patent 7,754,643 and has the characteristics as described therein.
  • the catalyst of the present invention possesses micro-mesoporous architecture as shown in Fig. 2 (high-resolution transmission electron micrograph) and an average pore diameter of 2.5 nanometers as revealed the the N 2 adsorption-desorption isotherm data (Fig. 3).
  • the catalyst is hydrophobic at reaction conditions and contains Lewis acid centers (Fig. 4; Pyridine-IR spectrum) due to tetra- coordinated Zn 2+ ions in the crystalline framework with the total acidity of the catalyst being in the range 1.5 - 2.2 mmol/g.
  • the degree of branching of the polyester is in the range 45 - 90%. In still another embodiment of the present invention, the viscosity of the polyester is in the range 0.02 - 0.1 dL/g.
  • Figure 2 High-resolution transmission electron micrographs of micro-mesoporous Fe-Zn double-metal cyanide catalyst.
  • FIG. 3 Nitrogen adsorption-desorption isotherms of Fe-Zn double metal cyanide catalyst. Inset shows pore size distribution.
  • the M-Zn double-metal cyanide catalysts with micro-mesoporous architecture are highly efficient and could be easily separated from the products for further reuse.
  • the prior art catalysts, mineral acid, organometallic compounds and enzymes needed additional process steps and efforts for catalyst separation. Moreover those catalysts cannot be recycled.
  • double-metal cyanide catalysts have been used in several acid catalyzed reactions, their application for the polycondensation of polycarboxylic acids with polyols resulting hyperbranched polyesters with low viscosity and high degree of branching and controlled gelation is disclosed in this invention.
  • An easily separable catalyst system e.g., the catalyst of the present invention is more advantageous.
  • the solid catalyst of the present invention is not only efficient but avoids the tedious process of catalyst recovery characteristic of the prior art processes.
  • the catalyst of the present invention yields hyperbranched polyesters of low viscosity, high degree of branching and controlled gelation from renewable feedstock at moderate temperatures, short period of reaction time and solvent-free conditions. It is a feature of the process of present invention that the catalyst is a solid and the reaction takes place in a heterogeneous condition. The solid catalyst can be easily separated from products by centrifugation-filtration/decantation for further reuse. It is another feature of the process of present invention that the process is eco-friendly, economical and generates no waste products unlike in the prior art processes in the process steps of catalyst separation /removal.
  • the catalyst of present invention It is the unique feature of the catalyst of present invention that its unusual surface hydrophobicity (that facilitates the adsorption of polycarboxylic acids and polyols but not the water formed as by-product in the polyesterification reaction) and micro-/mesoporous architecture (that controls the gelation and degree of branching).
  • the polyesterification reaction is conducted in the absence of a solvent.
  • the polyester is prepared from bio-derived polyol feedstocks and it is biodegradable.
  • the polyester has low viscosity unlike that in the prior art processes which produce gel.
  • Still another feature is that the reaction completes in a short period of times ca., 0.5 - 2 h. Still another feature of the present invention is that the number average molecular weight of the polymer can be tuned to be in the range 1000 - 6000 depending on reaction temperature and reaction time.
  • Example 1 The present invention is illustrated herein below with examples, which are illustrative only and should not be construed to limit the scope of the present invention in any manner.
  • Example 1
  • Poly(ethylene glycol)-block-poly(propylene glycol)- block-poly(ethylene glycol) (15 g) was separately dissolved in 2 ml of distilled water and 40 ml of tertiary-butanol (Solution- 3).
  • Solution-2 was added to solution-1 over 60 min at 50°C with vigorous stirring. White precipitation occurred during the addition.
  • solution-3 was added to the above reaction mixture over a period of 5 min and stirring was continued for further 1 h.
  • the solid cake formed was filtered, washed with distilled water (500 ml) and dried at 25°C for 2 days. This material was activated at 180°C for 4 h prior to using it in the reactions.
  • This example describes the preparation of hyperbranched polyester derived from bio-glycerol and succinic acid over Fe-Zn double-metal cyanide catalyst at 180°C.
  • Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester by reacting bio-glycerol with succinic acid at 180°C for 1.5 h over Fe-Zn double-metal cyanide catalyst.
  • Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round- bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester by reacting bio-glycerol with succinic acid at 180°C for 2 h over Fe-Zn double-metal cyanide catalyst.
  • Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round- bottom flask. The temperature was raised to 180°C. The reaction was carried out for 2 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester by reacting glycerol with succinic acid at 190°C for 1.5 h over Fe-Zn double-metal cyanide catalyst.
  • Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 190°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester by reacting glycerol with succinic acid in the molar ratio of 1 : 1.5 at 180°C for 1.5 h over Fe-Zn double-metal cyanide catalyst.
  • Glycerol (1 mol), succinic acid (1.5 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry- acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry-tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester by reacting glycerol with succinic acid in the molar ratio of 1 : 2 at 180°C for 1.5 h over Fe-Zn double-metal cyanide catalyst.
  • Glycerol (1 mol), succinic acid (2 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry- acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry-tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester by reacting bio-glycerol with adipic acid at 180°C for 2 h over Fe-Zn double-metal cyanide catalyst.
  • Glycerol (1 mol), adipic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 2 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester by reacting glycerol with adipic acid at 190°C for 1.5 h over Fe-Zn double-metal cyanide catalyst.
  • Glycerol (1 mol), adipic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 190°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester by reacting glycerol with adipic acid at a molar ratio of 1 : 2 at 180°C for 1.5 h over Fe-Zn double-metal cyanide catalyst.
  • Glycerol (1 mol), adipic acid (2 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry- acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry-tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester derived from sorbitol and succinic acid over Fe-Zn double-metal cyanide catalyst at 180°C.
  • Sorbitol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example illustrated the reusability of the catalyst recovered from example 3.
  • glycerol (1 mol), succinic acid (1 mol), recovered Fe-Zn double-metal cyanide catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13 C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry-tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
  • This example describes the preparation of hyperbranched polyester derived from glycerol and succinic acid over Co-Zn double-metal cyanide catalyst at 180°C.
  • Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was added to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid.
  • aG glycerol
  • S sorbitol
  • SA succinic acid
  • AA adipic acid
  • DB degree of branching
  • ⁇ inherent viscosity

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Polyesters Or Polycarbonates (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

An efficient, eco-friendly, solvent-free process for preparing hyperbranched polyesters by reacting polyols with polycarboxylic acid in the presence of heterogeneous, reusable, acid, crystalline, micro-mesoporous double-metal cyanide catalyst at moderate temperatures and short period of reaction time.

Description

PROCESS FOR PREPARING HYPERBRANCHED POLYESTERSFIELD OF THE
INVENTION
FIELD OF INVENTION:
The present invention relates to a process for preparing hyperbranched polyesters in the presence of a solid-acid catalyst.
More particularly, the present invention relates to an efficient, eco-friendly, solvent-free process for preparing hyperbranched polyesters comprising contacting polyols with polycarboxylic acids in the presence of a solid, acidic, crystalline, micro-mesoporous double- metal cyanide catalyst.
BACKGROUND OF THE INVENTION:
Hyperbranched polyesters belong to the family of dendrimers bearing large number of functional groups on their periphery. Despite their high polydispersities and low degree of branching, their chemical performances are quite similar to their dendrimer analogues. Topological specifics of hyperbranched polymers like high level of solubility and compatibility, low viscosity of solutions, resistance to aggregate even in concentrated solutions, ability to function as nanocontainers for substances sorbed inside, weak dependence of hydrodynamic volume on molecular weight and lump of free ends of chains with functional groups on their periphery open a new window for their diverse industrial use. Hyperbranched polymers find wide applicability as cosmetics, food additives, surfactants, lubricants, plasticizers, drug delivery agents, azeotropic phase separators, in orthopaedic and ophthalmic fields, building blocks for preparing poly-addition or poly-condensation polymers, additives in paints, coverings, adhesive promoters, sealants, casting elastomers, as rheology modifiers and as surface or interface modifiers. Discovery of unique properties of hyperbranched polyesters has expedited a rapid development in this area of materials. Hyperbranched polyesters derived from renewables broaden their applicability as novel, environmental-friendly materials for various applications.
l Polyesters are conventionally synthesized by polycondensation of di- or polycarboxylic acids with polyols. Industrially, aromatic polyesters, i.e., polyesters from aromatic dicarboxylic acids such as phthalic acid or terephthalic acid and alcohols such as 1,2-ethane diol, 1,2- or 1,3-propane diol or 1,4-butane diol, are more significant. The special applications of aliphatic, biodegradable polyesters derived from parent molecules like succinic acid, glutaric acid or adipic acid and alcohols such as 1,2-ethane diol, 1,2- or 1,3-propane diol, 1,3- or 1,4-butane diol, 1,5-pentane diol or 1,6-hexane diol are making these polymers more attractive in recent years.
US 6,441,126 and US 20100048813 describes a process for producing cross-linked, branched, aliphatic polyesters for gum base from glycerol and adipic acid at 150-200°C without any catalyst under solvent-free conditions.
EP 0799279 discloses the synthesis from an ethoxylated pentaerythritol and 2,2-dimethylol propanoic acid using conventional homogenous mineral acid catalyst, H2S04, at 140°C. Similarly several prior arts are available that disclose synthesis of polyesters from different reactants employing different catalysts, in solvent-free conditions or in the presence of solvent. Enzymatic and microbial catalysed processes also form part of prior art in this area. The results of such prior art processes are polyesters that donot possess the characteristics of low viscosity at a high degree of branching and with controlled gelation.
There are certain drawbacks with the prior art processes which include that the polyesters produced have high viscosity and lower degree of branching. The final product is always a gel. Controlled gelation at high conversions is an issue. Tuning the topological characteristics of hyperbranched polyesters is desirable to focus their application in specialized fields. Recovery of homogeneous catalysts and their reusability is also an issue with the mineral acid and organometal catalysts. Further, the organometal catalysts e.g., dibutyltin, butylstanoic acid etc are air and moisture sensitive. As water is formed as a by-product in the polyesterification reaction, the organometal catalysts soon get deactivated. Corrosion of reactors and pipe lining is a problem with mineral acid catalysts. Although the reaction occurs at mild temperature while using enzyme catalysts, long reaction times of nearly 24 h are needed. A solid catalyst-based process has several engineering, environmental and economic advantages. The solid catalyst can be easily separated and reused in subsequent recycles. It is therefore desirable to develop an efficient solid catalyst-based process for producing hyperbranched polyesters of low-viscosity and high degree of branching with controlled gelation to achieve polyesters for speciality applications.
Double-metal cyanides were used as catalysts for the preparation of polyether polyols (WO 2009055436; US 6624286; Chen et al., J Polym Sci A Polym Chem., Year 2004, Vol. 42, pp.6519), alternative copolymerization of epoxides and C02 (US Patent Nos. 6,359,101, 6,953,765 and 6,852,663) and biodiesel and biolubricants manufacture by transesterification/esterification of vegetable oils or animal fat (monohydric carboxylic acid) with monohydric alcohols (US Patent Nos. 7,754,643, 7,482,480 and 7,842,653; EP 1 733 788; Sreeprasanth et al., Appl. Catal. A: Gen., Year 2006, Vol. 314, pp. 148). However, their application for the preparation of hyperbranched polyesters is not disclosed so far.
It is surprising that double metal cyanide catalysts with cubic crystallite structure, micro- mesoporous architexture, strong Lewis acid centers and surface hydrophobicity exhibit high catalytic activity to produce hyperbranched polyesters especially those with low-viscosity, high degree of branching and controlled gelation.
Double metal cyanide catalysts of different crystallite structures (monoclinic) and amorphous nature have been used for the preparation of polyesters and other hybrid polymers as described in the following prior arts.
DE 10 2008 004 343 Al discloses a process for preparing polyester alcohol useful to prepare polyurethane foams and thermoplastic polyurethane elastomers, comprising catalytic conversion of at least a difunctional carboxylic acid with at least a difunctional alcohol, where at least a part of the reaction is carried out in the presence of a polymetal cyanide or a double metal cyanide catalyst usually in an amount up to 1% by weight of the reaction mixture. The polycondensation reaction can be performed both in presence and in absence of a solvent at temperature 160 - 280°C. This disclosure is specific for conversion of dicarboxylic compounds with dihydroxy compounds. The product is a linear polyester whereas the instant invention describes a hyperbranched polyester with low-viscosity and high degree of branching at controlled gelation. WO 2011/137011 Al tells a process for preparing a hybrid polyester-polyether polyols comprising reacting a carboxyl group-containing component and an epoxide, optionally in the presence of one or more double metal cyanide catalyst, a superacid catalyst, a metal salt of a superacid catalyst and/or a tertiary amine catalyst, under conditions such that a hybrid polyester-polyether polyol is formed. Further, the said reaction is carried out in presence of solvent such as toluene. The process results in products having narrow polydispersity, a low acid number and unsaturation and reduced byproducts formation, particularly when the metal cyande catalyst is employed. The product is a hybrid polyester-polyether-polyol, different from that of the present invention. US 7842653 describes a process for preparing lubricants wherein the said process comprises contacting a monocarboyxlic vegetable oil or fat with a monohydric C6 - C8 alcohol in the presence of a double-metal cyanide catalyst wherein the vegetable oil/fat to alcohol molar ratio being 1 : 6, reaction temperature being in the range 150 - 200°C and reaction time being in the range 3 - 6 hrs. The product is a monoester.
WO 2011/075343 Al discloses a process to convert a secondary hydroxyl-capped polyol to a primary hydroxyl-capped polyol comprises reacting a polyether polyol, a polyester polyol, polyether-ester polyol or a polyether-polyester polyol with a cyclic anhydride of a polycarboxylic acid to form a half acid ester, followed by the reacting the half acid ester with ethylene oxide, to form a polyester polyol or a polyether-polyester polyol. Both steps are carried out in the presence of an amine catalyst and a double metal cyande catalyst. The latter catalyst useful for polymerization of epoxides generally may include an organic complex agent such a diglyme.
CN101570595 discloses a terpolymer containing polyester chain links and polycarbonate chain links and a synthetic method thereof, which comprises the mixing of zinc-cobalt double metal cyanide complex catalyst, cyclohexene oxide and dicarboxylic anhydride in a solvent. The double metal cyanide catalyst used in the present invention is unique and thereby shows efficient catalytic activity for the preparation of hyperbranched polyesters. The unusual surface hydrophobicity of the catalyst facilitates the adsorption of polycarboxylic acids and polyols but not the water formed as by-product in the esterification reaction and micro- mesoporous architecture controls the gelation and degree of branching. OBJECTIVES OF THE INVENTION:
The main object of present invention is to provide a process for preparing hyperbranched polyesters of low viscosity, high degree of branching and controlled gelation making use of an efficient, reusable, heterogeneous acid catalyst.
Another object of present invention is to provide an efficient, eco-friendly process for the synthesis of hyperbranched polyesters from renewables in presence of a solid, reusable, acid catalyst.
Yet another objective is to describe a process for providing hyperbranched polyesters at moderate temperatures, short period of reaction time and solvent-free conditions.
SUMMARY OF THE INVENTION:
Accordingly, the present invention provides an efficient, eco-friendly, solvent-free a process for preparing hyper branched polyesters having degree of branching in range 45 - 90% and inherent viscosity in the range 0.02 - 0.1 dL/g and the said process comprising the steps of:
(a) contacting a polyol with a polycarboxylic acid in the presence of a double-metal cyanide catalyst wherein the polyol to polycarboxylic acid molar ratio is in the range 1:1 to 1:2 and catalyst in the range 2 - 5 wt% of reactants;
(b) subjecting the reaction mixture as obtained in step (a) at temperature in the range
of 160 to 200°C and for a reaction period of 0.5 - 2 h to obtain polyesters;
(c) dissolving the reaction mixture obtained in step (b) in a polar solvent like
acetone and separating the catalyst by filtration;
(d) adding a non-polar solvent like heptane to the reaction mixture obtained from step (c) to precipitate out and isolate the hyper branched polyesters.
In one embodiment of the present invention the chemical formula of double metal cyanide Catalyst used in step (a) is :
Zn3M2(CN)„(ROH).xZnCl2.yH20
wherein R is tertiary-butyl; M is a transition metal ion selected from the group consisting of Fe and Co; x varies from 0 to 0.5, y varies from 3 - 5 and n is 10 or 12.
In another embodiment of the present invention the polyol used in step (a) has atlest two alcoholic groups. In another embodiment of the present invention the polyols is selected from the group consisting of glycerol, sorbitol, mannitol, glucose and sucrose .
In another embodiment of the present invention the polycarboxylic acid used in step (a) contains at least two carboxylic groups.
In another embodiment of the present invention the polycarboxylic acid used in step (a) is selected from the group consisting of succinic acid and adipic acid.
In another embodiment of the present invention the solid catalyst is reusable.
In another embodiment of the present invention the isolated yield of polyester is in the range 50 - 90 wt%.
In an embodiment of the present invention, the double-metal cyanide catalyst was prepared as per the US patent 7,754,643 and has the characteristics as described therein.
In an embodiment of the present invention, the catalyst is crystalline and has cubic structure showing sharp and intense powder X-ray diffraction peaks at 2Θ = 11.34, 13.94, 14.22° with corresponding d-spacings of 7.79, 6.22, 6.34 angstroms, respectively as shown in Fig. 1. In yet another embodiment, the catalyst of the present invention possesses micro-mesoporous architecture as shown in Fig. 2 (high-resolution transmission electron micrograph) and an average pore diameter of 2.5 nanometers as revealed the the N2 adsorption-desorption isotherm data (Fig. 3).
In still another embodiment of the present invention the catalyst is hydrophobic at reaction conditions and contains Lewis acid centers (Fig. 4; Pyridine-IR spectrum) due to tetra- coordinated Zn2+ ions in the crystalline framework with the total acidity of the catalyst being in the range 1.5 - 2.2 mmol/g.
In yet another embodiment of the present invention, the degree of branching of the polyester is in the range 45 - 90%. In still another embodiment of the present invention, the viscosity of the polyester is in the range 0.02 - 0.1 dL/g.
Description of figures: Figure 1: X-ray diffraction pattern of Fe-Zn double-metal cyanide catalyst. Catalyst is crystalline and has cubic structure showing sharp and intense powder X-ray diffraction peaks at 2Θ = 11.34, 13.94, 14.22° with corresponding d-spacings of 7.79, 6.22, 6.34 angstroms, respectively. Figure 2: High-resolution transmission electron micrographs of micro-mesoporous Fe-Zn double-metal cyanide catalyst.
Figure 3: Nitrogen adsorption-desorption isotherms of Fe-Zn double metal cyanide catalyst. Inset shows pore size distribution.
Figure 4: Pyridine-IR spectra of Fe-Zn double metal cyanide catalyst. DETAILED DESCRIPTION OF THE INVENTION
In the investigations leading to the present invention, it was found that the M-Zn double-metal cyanide catalysts with micro-mesoporous architecture are highly efficient and could be easily separated from the products for further reuse. The prior art catalysts, mineral acid, organometallic compounds and enzymes needed additional process steps and efforts for catalyst separation. Moreover those catalysts cannot be recycled. Although double-metal cyanide catalysts have been used in several acid catalyzed reactions, their application for the polycondensation of polycarboxylic acids with polyols resulting hyperbranched polyesters with low viscosity and high degree of branching and controlled gelation is disclosed in this invention. An easily separable catalyst system e.g., the catalyst of the present invention is more advantageous. The solid catalyst of the present invention is not only efficient but avoids the tedious process of catalyst recovery characteristic of the prior art processes.
The catalyst of the present invention yields hyperbranched polyesters of low viscosity, high degree of branching and controlled gelation from renewable feedstock at moderate temperatures, short period of reaction time and solvent-free conditions. It is a feature of the process of present invention that the catalyst is a solid and the reaction takes place in a heterogeneous condition. The solid catalyst can be easily separated from products by centrifugation-filtration/decantation for further reuse. It is another feature of the process of present invention that the process is eco-friendly, economical and generates no waste products unlike in the prior art processes in the process steps of catalyst separation /removal.
It is the unique feature of the catalyst of present invention that its unusual surface hydrophobicity (that facilitates the adsorption of polycarboxylic acids and polyols but not the water formed as by-product in the polyesterification reaction) and micro-/mesoporous architecture (that controls the gelation and degree of branching).
Yet another feature of the present invention is that the polyesterification reaction is conducted in the absence of a solvent. Yet another feature of the present invention is that the polyester is prepared from bio-derived polyol feedstocks and it is biodegradable.
It is a feature of the process of present invention that the polyester has low viscosity unlike that in the prior art processes which produce gel.
Still another feature is that the reaction completes in a short period of times ca., 0.5 - 2 h. Still another feature of the present invention is that the number average molecular weight of the polymer can be tuned to be in the range 1000 - 6000 depending on reaction temperature and reaction time.
The present invention is illustrated herein below with examples, which are illustrative only and should not be construed to limit the scope of the present invention in any manner. Example 1
This example illustrates the preparation of Fe-Zn double metal cyanide catalyst used in the present invention. K4[Fe(CN)6] (0.01 mol) was dissolved in double distilled water (40 ml) (Solution-1). ZnCl2 (0.1 mol) was dissolved in a mixture of distilled water (100 ml) and tertiary-butanol (20 ml) (Solution-2). Poly(ethylene glycol)-block-poly(propylene glycol)- block-poly(ethylene glycol) (EO20-PO70-EO20; molecular weight of about 5800) (15 g) was separately dissolved in 2 ml of distilled water and 40 ml of tertiary-butanol (Solution- 3). Solution-2 was added to solution-1 over 60 min at 50°C with vigorous stirring. White precipitation occurred during the addition. Then, solution-3 was added to the above reaction mixture over a period of 5 min and stirring was continued for further 1 h. The solid cake formed was filtered, washed with distilled water (500 ml) and dried at 25°C for 2 days. This material was activated at 180°C for 4 h prior to using it in the reactions. Refer US Patent Nos. 7,754,643 and Figure 1.
Example 2
This example illustrates the preparation of Co-Zn double metal cyanide catalyst used in the present invention. K4[Co(CN)6] (0.01 mol) was dissolved in double distilled water (40 ml) (Solution-1). ZnCb (0.1 mol) was dissolved in a mixture of distilled water (100 ml) and tertiary-butanol (20 ml) (Solution-2). Poly(ethylene glycol)-block-poly(propylene glycol)- block-poly(ethylene glycol) (EO20-PO70-EO20; molecular weight of about 5800) (15 g) was separately dissolved in 2 ml of distilled water and 40 ml of tertiary-butanol (Solution-3). Solution-2 was added to solution-1 over 60 min at 50°C with vigorous stirring. White precipitation occurred during the addition. Then, solution-3 was added to the above reaction mixture over a period of 5 min and stirring was continued for further 1 h. The solid formed was filtered, washed with distilled water (500 ml) and dried at 25°C. This material was activated at 180°C for 4 h prior to using it in the reactions. Refer US Patent Nos. 7,754,643
Example 3
This example describes the preparation of hyperbranched polyester derived from bio-glycerol and succinic acid over Fe-Zn double-metal cyanide catalyst at 180°C. Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
Example 4
This example describes the preparation of hyperbranched polyester by reacting bio-glycerol with succinic acid at 180°C for 1.5 h over Fe-Zn double-metal cyanide catalyst. Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round- bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
Example 5
This example describes the preparation of hyperbranched polyester by reacting bio-glycerol with succinic acid at 180°C for 2 h over Fe-Zn double-metal cyanide catalyst. Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round- bottom flask. The temperature was raised to 180°C. The reaction was carried out for 2 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer. Example 6
This example describes the preparation of hyperbranched polyester by reacting glycerol with succinic acid at 190°C for 1.5 h over Fe-Zn double-metal cyanide catalyst. Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 190°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
Example 7
This example describes the preparation of hyperbranched polyester by reacting glycerol with succinic acid in the molar ratio of 1 : 1.5 at 180°C for 1.5 h over Fe-Zn double-metal cyanide catalyst. Glycerol (1 mol), succinic acid (1.5 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry- acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry-tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
Example 8
This example describes the preparation of hyperbranched polyester by reacting glycerol with succinic acid in the molar ratio of 1 : 2 at 180°C for 1.5 h over Fe-Zn double-metal cyanide catalyst. Glycerol (1 mol), succinic acid (2 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry- acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry-tetrahydrofuran solvent) was determined using a Ubbelhode viscometer. Example 9
This example describes the preparation of hyperbranched polyester by reacting bio-glycerol with adipic acid at 180°C for 2 h over Fe-Zn double-metal cyanide catalyst. Glycerol (1 mol), adipic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 2 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
Example 11
This example describes the preparation of hyperbranched polyester by reacting glycerol with adipic acid at 190°C for 1.5 h over Fe-Zn double-metal cyanide catalyst. Glycerol (1 mol), adipic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 190°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
Example 12
This example describes the preparation of hyperbranched polyester by reacting glycerol with adipic acid at a molar ratio of 1 : 2 at 180°C for 1.5 h over Fe-Zn double-metal cyanide catalyst. Glycerol (1 mol), adipic acid (2 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1.5 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry- acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry-tetrahydrofuran solvent) was determined using a Ubbelhode viscometer. Example 13
This example describes the preparation of hyperbranched polyester derived from sorbitol and succinic acid over Fe-Zn double-metal cyanide catalyst at 180°C. Sorbitol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
Example 14
This example illustrated the reusability of the catalyst recovered from example 3. In a typical reaction, glycerol (1 mol), succinic acid (1 mol), recovered Fe-Zn double-metal cyanide catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry-tetrahydrofuran solvent) was determined using a Ubbelhode viscometer.
Example 15
This example describes the preparation of hyperbranched polyester derived from glycerol and succinic acid over Co-Zn double-metal cyanide catalyst at 180°C. Glycerol (1 mol), succinic acid (1 mol), catalyst (3 wt% of reaction mixture) were taken in a glass round-bottom flask. The temperature was raised to 180°C. The reaction was carried out for 1 h at atmospheric pressure. After cooling to 25°C, about 10 ml of dry-acetone was added to the contents of the flask. Catalyst was separated by centrifugation followed by filtration. The polymer was reprecipitated by adding 20 ml of n-heptane. The product polyester is a clear liquid. 13C NMR spectroscopy was used to analyze the degree of branching and viscosity (in dry- tetrahydrofuran solvent) was determined using a Ubbelhode viscometer. The characteristics of different hyperbranched polyesters obtained from Examples 3 listed in Table 1.
Table 1. Characteristics of different hyperbranched polyesters*
Figure imgf000015_0001
aG = glycerol, S = sorbitol, SA = succinic acid, AA= adipic acid, DB= degree of branching, η = inherent viscosity.
Many modifications, substitutions and variations of the present invention are possible and apparent to those skilled in the art. The present invention can be practiced other than specifically described in the examples and should be limited in scope and breadth only by the appended claims. ADVANTAGES OF THE INVENTION:
Advantages of instant invention are as following:
1. Heterogeneous, solid acid catalyst-based process
2. Reusable catalyst process
3. Solvent-free process
4. Low viscosity product with high degree of branching
5. Reaction at moderate temperatures and for short periods of time.
6. Applicable to a large number of polyols and polycarboxylic acids
7. Flexible process with tunability of final ester product properties.

Claims

We claim:
1. A process for preparing hyper-branched polyesters having degree of branching in range 45 - 90% and inherent viscosity in the range 0.02 - 0.1 dL/g and the said process comprising the steps of:
(a) contacting a polyol with a polycarboxylic acid in the presence of a double-metal cyanide catalyst wherein the polyol to polycarboxylic acid molar ratio is in the range 1:1 to 1:2 and catalyst in the range 2 - 5 wt% of reactants;
(b) subjecting the reaction mixture as obtained in step (a) at temperature in the range of 160 to 200°C and for a reaction period of 0.5 - 2 h to obtain polyesters;
(c) dissolving the reaction mixture obtained in step (b) in a polar solvent like acetone and separating the catalyst by filtration;
(d) adding a non-polar solvent like heptane to the reaction mixture obtained from step (c) to precipitate out and isolate the hyper-branched polyesters.
2. The process as claimed in claim 1, wherein the chemical formula of double metal cyanide Catalyst used in step (a) is : Zn3M2(CN)„(ROH).xZnCl2.yH20;
wherein R is tertiary-butyl; M is a transition metal ion selected from the group consisting of Fe and Co; x varies from 0 to 0.5, y varies from 3 - 5 and n is 10 or 12.
3. The process as claimed in claims 1, wherein the catalyst possesses micro-mesoporous architecture and an average pore diameter of 2.5 nanometers.
4. The process as claimed in claims 1, wherein the catalyst is hydrophobic at reaction conditions and contains Lewis acid centers due to tetra-coordinated Zn2+ ions in the crystalline framework with the total acidity being in the range 1.5 - 2.2 mmol/g.
5. The process as claimed in claim 1, wherein the polyol used in step (a) has at least two alcoholic groups.
6. The process as claimed in claim 1, wherein the polyols is selected from the group consisting of glycerol, sorbitol, mannitol, glucose and sucrose.
7. The process as claimed in claim 1, wherein the polycarboxylic acid used in step (a) contains at least two carboxylic groups.
8. The process as claimed in claim 1, wherein the polycarboxylic acid used in step (a) is selected from the group consisting of succinic acid and adipic acid.
9. The process as claimed in claim 1, wherein the solid catalyst is reusable.
10. The process as claimed in claim 1, wherein the isolated yield of polyester is in the range 50 - 90 wt%.
PCT/IN2012/000125 2011-02-23 2012-02-23 Process for preparing hyperbranched polyestersfield of the invention WO2012114357A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
EP12715442.5A EP2678370B1 (en) 2011-02-23 2012-02-23 Process for preparing hyperbranched polyesters
US14/001,322 US9334361B2 (en) 2011-02-23 2012-02-23 Process for preparing hyperbranched polyesters
BR112013021671A BR112013021671A2 (en) 2011-02-23 2012-02-23 process for preparing a hyperbranched polyester field of the invention
CN201280018710.6A CN103476824B (en) 2011-02-23 2012-02-23 Process for preparing hyperbranched polyestersfield
RU2013142982/04A RU2596831C2 (en) 2011-02-23 2012-02-23 Method of producing hyperbranched polyesters

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN471/DEL/2011 2011-02-23
IN471DE2011 2011-02-23

Publications (2)

Publication Number Publication Date
WO2012114357A1 true WO2012114357A1 (en) 2012-08-30
WO2012114357A8 WO2012114357A8 (en) 2013-10-10

Family

ID=45976982

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IN2012/000125 WO2012114357A1 (en) 2011-02-23 2012-02-23 Process for preparing hyperbranched polyestersfield of the invention

Country Status (6)

Country Link
US (1) US9334361B2 (en)
EP (1) EP2678370B1 (en)
CN (1) CN103476824B (en)
BR (1) BR112013021671A2 (en)
RU (1) RU2596831C2 (en)
WO (1) WO2012114357A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013175509A1 (en) 2012-05-22 2013-11-28 Council Of Scientific And Industrial Research Process for preparing biodegradable lubricant base oils
CN110922676A (en) * 2019-10-30 2020-03-27 中化石化销售有限公司 Preparation method of foaming agent master batch

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MY173189A (en) * 2015-10-07 2020-01-03 Malaysian Palm Oil Board Metal-incorporated hyperbranched polyester-polyol
CN109763188B (en) * 2018-12-13 2020-06-12 东华大学 Fiber containing hyperbranched hybrid porous material and preparation method thereof
CN109706535B (en) * 2018-12-13 2020-08-14 东华大学 Polyacrylonitrile fiber containing hyperbranched polymer and preparation method thereof
CN114835911B (en) * 2022-05-18 2023-11-03 中南民族大学 Sorbitol type hyperbranched polyester, preparation method, application and polypropylene composite material
CN115710348B (en) * 2022-09-28 2023-09-12 北京工商大学 Preparation method and application of microcrystalline cellulose grafted hydroxyl-terminated hyperbranched polyester

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0799279A1 (en) 1994-12-21 1997-10-08 Perstorp Ab A thermosetting material
US6359101B1 (en) 1999-12-15 2002-03-19 Synuthane International, Inc. Preparing polyether polyols with DMC catalysts
US6441126B1 (en) 1999-04-26 2002-08-27 Eastman Chemical Company Branched aliphatic polyesters
US6624286B2 (en) 1997-10-13 2003-09-23 Bayer Aktiengesellschaft Double-metal cyanide catalysts containing polyester for preparing polyether polyols
US6852663B2 (en) 2001-05-07 2005-02-08 Bayer Aktiengesellschaft Double-metal cyanide catalysts for preparing polyether polyols
US6953765B2 (en) 2001-05-07 2005-10-11 Bayer Aktiengesellschaft Double metal cyanide catalysts for preparing polyether polyols
EP1733788A1 (en) 2005-06-16 2006-12-20 Council Of Scientific & Industrial Research An improved process for the preparation of lubricants by using double metal cyanid catatysts
US20080108719A1 (en) * 1999-10-25 2008-05-08 Geiger Eric J Phthalic Anhydride Based Polyester-Ether Polyols and Double Metal Cyanide Catalyst System for Preparing Same
DE102008004343A1 (en) 2007-01-19 2008-07-24 Basf Se Preparing polyester alcohol, useful to prepare polyurethane foams and thermoplastic polyurethane elastomers, comprises catalytic conversion of at least a difunctional carboxylic acid with at least a difunctional alcohol
US7482480B2 (en) 2005-10-10 2009-01-27 Council Of Scientific & Industrial Research Process for the preparation of hydrocarbon fuel
CN101570595A (en) 2009-05-22 2009-11-04 浙江大学 Terpolymer containing polyester chain links and polycarbonate chain links and synthetic method thereof
US20100048813A1 (en) 2006-11-14 2010-02-25 Basf Se Highly-branched or hyper-branched polyester and the production and application thereof
US7754643B2 (en) 2005-10-07 2010-07-13 Council Of Scientific & Industrial Research Transesterification catalyst and a process for the preparation thereof
WO2011075343A1 (en) 2009-12-17 2011-06-23 Dow Global Technologies Inc. Ethylene oxide capping of secondary hydroxyl polyols
WO2011137011A1 (en) 2010-04-29 2011-11-03 Dow Global Technologies Llc Hybrid polyester-polyether polyols

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5767323A (en) * 1995-12-22 1998-06-16 Arco Chemical Technology, L.P. Process for preparing polyoxyalkylene polyether polyols having low levels of transition metals through double metal cyanide complex polyoxyalkylation

Patent Citations (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0799279A1 (en) 1994-12-21 1997-10-08 Perstorp Ab A thermosetting material
US6624286B2 (en) 1997-10-13 2003-09-23 Bayer Aktiengesellschaft Double-metal cyanide catalysts containing polyester for preparing polyether polyols
US6441126B1 (en) 1999-04-26 2002-08-27 Eastman Chemical Company Branched aliphatic polyesters
US20080108719A1 (en) * 1999-10-25 2008-05-08 Geiger Eric J Phthalic Anhydride Based Polyester-Ether Polyols and Double Metal Cyanide Catalyst System for Preparing Same
US6359101B1 (en) 1999-12-15 2002-03-19 Synuthane International, Inc. Preparing polyether polyols with DMC catalysts
US6852663B2 (en) 2001-05-07 2005-02-08 Bayer Aktiengesellschaft Double-metal cyanide catalysts for preparing polyether polyols
US6953765B2 (en) 2001-05-07 2005-10-11 Bayer Aktiengesellschaft Double metal cyanide catalysts for preparing polyether polyols
EP1733788A1 (en) 2005-06-16 2006-12-20 Council Of Scientific & Industrial Research An improved process for the preparation of lubricants by using double metal cyanid catatysts
US7842653B2 (en) 2005-06-16 2010-11-30 Council Of Scientific & Industrial Research Process for the preparation of lubricants
US7754643B2 (en) 2005-10-07 2010-07-13 Council Of Scientific & Industrial Research Transesterification catalyst and a process for the preparation thereof
US7482480B2 (en) 2005-10-10 2009-01-27 Council Of Scientific & Industrial Research Process for the preparation of hydrocarbon fuel
US20100048813A1 (en) 2006-11-14 2010-02-25 Basf Se Highly-branched or hyper-branched polyester and the production and application thereof
DE102008004343A1 (en) 2007-01-19 2008-07-24 Basf Se Preparing polyester alcohol, useful to prepare polyurethane foams and thermoplastic polyurethane elastomers, comprises catalytic conversion of at least a difunctional carboxylic acid with at least a difunctional alcohol
WO2009055436A1 (en) 2007-10-22 2009-04-30 Stepan Company Phthalic anhydride based polyester-ether polyols and double metal cyanide catalyst system for preparing same
CN101570595A (en) 2009-05-22 2009-11-04 浙江大学 Terpolymer containing polyester chain links and polycarbonate chain links and synthetic method thereof
WO2011075343A1 (en) 2009-12-17 2011-06-23 Dow Global Technologies Inc. Ethylene oxide capping of secondary hydroxyl polyols
WO2011137011A1 (en) 2010-04-29 2011-11-03 Dow Global Technologies Llc Hybrid polyester-polyether polyols

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
CHEN ET AL., J POLYM SCI A POLYM CHEM., vol. 42, 2004, pages 6519
SREEPRASANTH ET AL., APPL. CATAL. A: GEN., vol. 314, 2006, pages 148

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013175509A1 (en) 2012-05-22 2013-11-28 Council Of Scientific And Industrial Research Process for preparing biodegradable lubricant base oils
US9174919B2 (en) 2012-05-22 2015-11-03 Council Of Scientific And Industrial Research Process for preparing biodegradable lubricant base oils
CN110922676A (en) * 2019-10-30 2020-03-27 中化石化销售有限公司 Preparation method of foaming agent master batch
CN110922676B (en) * 2019-10-30 2022-09-16 中化石化销售有限公司 Preparation method of foaming agent master batch

Also Published As

Publication number Publication date
CN103476824B (en) 2015-06-17
RU2013142982A (en) 2015-03-27
EP2678370A1 (en) 2014-01-01
RU2596831C2 (en) 2016-09-10
EP2678370B1 (en) 2016-03-30
CN103476824A (en) 2013-12-25
BR112013021671A2 (en) 2016-11-01
WO2012114357A8 (en) 2013-10-10
US9334361B2 (en) 2016-05-10
US20130331542A1 (en) 2013-12-12

Similar Documents

Publication Publication Date Title
US9334361B2 (en) Process for preparing hyperbranched polyesters
Helou et al. Poly (carbonate-urethane): an isocyanate-free procedure from α, ω-di (cyclic carbonate) telechelic poly (trimethylene carbonate) s
Labet et al. Synthesis of polycaprolactone: a review
CN104797627B (en) Aliphatic Polycarbonate Copolymers with HMW and preparation method thereof
WO2010069000A1 (en) Organometallic catalyst and preparation thereof
WO2001087481A1 (en) Catalyst for esterification and transesterification and process for producing ester
US8816020B2 (en) Method to produce polyurea and polyurethane by using liquid plant oil based polyol
EP3048128B1 (en) Method for preparing polyalkylene carbonate resin
EP3048129B1 (en) Organic zinc catalyst, preparation method therefor, and method for preparing polyalkylene carbonate resin by using same
JP2016527376A (en) Macropolyol composed of aliphatic polycarbonate and aromatic polyester copolymer thereof
Sebastian et al. Influence of method of preparation of solid, double-metal cyanide complexes on their catalytic activity for synthesis of hyperbranched polymers
Debuissy et al. Lipase-catalyzed synthesis of biobased and biodegradable aliphatic copolyesters from short building blocks. Effect of the monomer length
Howard et al. Polymer-supported metal catalysts for the heterogeneous polymerisation of lactones
CN107955142A (en) Preparation method containing isobide polyester
Dhaini et al. Recent advances in polyhydroxyalkanoates degradation and chemical recycling
KR101693546B1 (en) Poly lactic acid based biodegradable resin composition with good processability and flexibility and biodegradable film prepared therefrom
WO2015013572A1 (en) Improved process for the preparation of modified poly(alkylene terephthalate) employing an in-situ titanium-containing catalyst
EP1585779A1 (en) Catalyst complex for catalysing esterification and trans-esterification reactions and process for esterification /trans-esterification using the same
Werlinger et al. Approach to Circular Chemistry Preparing New Polyesters from Olive Oil
Sebastian et al. Solid, double-metal cyanide catalysts for synthesis of hyperbranched polyesters and aliphatic polycarbonates
Chaeichian et al. Synthesis of unsaturated polyester resins from PET wastes: Effect of a novel co-catalytic system on glycolysis and polyesterification reactions
AU2018357067A1 (en) Method for quenching a polymerisation process
KR102125050B1 (en) Organic zinc catalyst, preparation method of the catalyst and production method of poly(alkylene carbonate) resin over the catalyst
US9487622B2 (en) Process for the preparation of modified poly(alkylene terephthalate) employing an in-situ titanium-containing catalyst
KR20160006222A (en) Improved process for the preparation of modified poly(alkylene terephthalate) employing an in-situ titanium-containing catalyst

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12715442

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 14001322

Country of ref document: US

Ref document number: 2012715442

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2013142982

Country of ref document: RU

Kind code of ref document: A

REG Reference to national code

Ref country code: BR

Ref legal event code: B01A

Ref document number: 112013021671

Country of ref document: BR

ENP Entry into the national phase

Ref document number: 112013021671

Country of ref document: BR

Kind code of ref document: A2

Effective date: 20130823