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
  • C08G63/02—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
  • C08G63/18—Dicarboxylic acids and dihydroxy compounds the acids or hydroxy compounds containing carbocyclic rings
  • C08G63/181—Acids containing aromatic rings
  • C08G63/185—Acids containing aromatic rings containing two or more aromatic rings
  • C08G63/187—Acids containing aromatic rings containing two or more aromatic rings containing condensed aromatic rings
  • C08G63/189—Acids containing aromatic rings containing two or more aromatic rings containing condensed aromatic rings containing a naphthalene ring
• • 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
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/42—Polycondensates having carboxylic or carbonic ester groups in the main chain
  • C08G18/4205—Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups
  • C08G18/4208—Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups containing aromatic groups
  • C08G18/4211—Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups containing aromatic groups derived from aromatic dicarboxylic acids and dialcohols
  • C08G18/4216—Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups containing aromatic groups derived from aromatic dicarboxylic acids and dialcohols from mixtures or combinations of aromatic dicarboxylic acids and aliphatic dicarboxylic acids and dialcohols
• • 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
  • C08G2110/00—Foam properties
  • C08G2110/0025—Foam properties rigid
• • 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

Definitions

• This invention relates to the preparation of poly(alkylene polyaromatic dicarboxylate) ester based polyester polyols and the use thereof in the preparation of rigid polyurethane and polyisocyanurate foams.
• the invention more specifically relates to polyester polyols produced from reacting polyethylene naphthalate.
• PUR polyurethane
• PIR polyisocyanurate
• a wide variety of polyols have been used as one of the components in the preparation of rigid polyurethane foams, including polyols from different waste streams.
• the polyols are usually polyether alcohols or polyester alcohols, or a mixture of the two. Both aliphatic and aromatic polyester polyalcohols are in use. They are the reaction products of an esterification of a dicarboxylic acid or an anhydride with glycols (primary/secondary). More often a transesterification process is used.
• Aromatic polyester polyols used in rigid PUR/PIR foams are typically based on production waste streams of dimethyl terephtalate (DMT).
• DMT dimethyl terephtalate
• PET polyethylene terephtalate
• Depolymerization of production waste streams or post consumer waste from e.g. PET bottles is a known method in the preparation of a polyester polyol.
• PEN poly(ethylene naphthalate)
• PEN poly(ethylene naphthalate)
• PEN poly(ethylene naphthalate)
• Rigid polyurethane or polyisocyanurate foams made using this polyester polyol show excellent mechanical stability, good fire performance and low smoke generation together with a low thermal conductivity.
• the poly(alkylene polyaromatic dicarboxylate) ester preferably used in the present invention is poly(ethylene 2,6-naphthalate).
• Other isomers of this polymer, or copolymers with e.g. polyethylene terephtalate) (PET), poly(butylene terephthalate) (PBT) or poly(butylene naphthalate) can also be employed, as well as the polyesters based on dicarboxylates with a multi ring structure (e.g. anthracene, phenantrene) .and their copolymers.
• the polyester polyol is prepared by a two step process.
• the polyester is depolymerised in the presence of a glycol.
• a glycol can be, for example, 1,4- butanediol, diethyleneglycol (DEG) or dipropyleneglycol (DPG).
• DEG diethyleneglycol
• DPG dipropyleneglycol
• Most suitable as the diol is DEG and it is preferably used in an amount in excess of that required for digestion.
• the preferred catalyst is tetra-N-butyltitanate (TBT). Zinc oxide or mangane acetate can also be employed.
• TBT tetra-N-butyltitanate
• Zinc oxide or mangane acetate can also be employed.
• the depolymerization is carried out at such temperature that the polyester dissociates and the core units are obtained.
• the process is typically in the temperature range of 150 to 350°C, preferably about 240°C.
• the process is typically carried out at atmospheric pressure. However, it will be obvious that pressures higher than atmospheric can be used. At higher pressures the reaction temperature can be increased significantly, thus shortening the reaction time.
• the obtained reaction mixture contains the esterification product from the polyaromatic dicarboxylate and the used glycol, together with the diol of the alkylene chain between the aromatic rings. Very often, excess glycols are present.
• the product from this first step contains naphthalate polyols, unreacted glycols and ethylene glycol from the PEN. During the depolymerisation and esterification, removal of the formed ethylene glycol by vacuum distillation is possible.
• the mixture is further transesterified by addition of other polycarboxyhc acids, anhydrides or esters and a polyhydric alcohol.
• This further esterification brings the final polyester polyol in the desired viscosity range.
• the total content of polyester polymer used in the synthesis of the polyester polyol is typically in the range 5 to 50 wt%, preferably 10 to 40 wt%.
• the polycarboxyhc acid and the polyhydric alcohol are added at a temperature in the range of 80 to 240°C, preferably 100 to 180°C.
• polycarboxyhc acid component or its derivatives are adipic acid, glutaric acid and anhydride, succinic acid, oxalic acid, malonic acid, suberic acid, azelaic acid, sebacic acid, phtalic acid, phtalic anhydride, pyromellitic anhydride.
• polyfunctional alcohol glycols are preferred. They can be a simple glycol of general formula C n H2 n (OH)2 or polyglycols with intervening ether linkages, as represented in the general formula C n H2 n O x (OH)2. They also may contain heteroatoms.
• the polycarboxyhc component and polyhydric alcohol may include substituents which are inert in the reaction, e.g. chlorine and bromine substituents, and/or may be unsaturated.
• suitable polyhydric alcohols are alkylene glycols and oxyalkylene glycols, such as ethylene glycol, diethylene glycol and higher polyethylene glycols, propylene glycol, dipropyleneglycol and higher propylene glycols, glycerol, pentaerythritol, trimethylolpropane, sorbitol and mannitol.
• the two steps described above can also be carried out in a single step process.
• the depolymerisation of the polyester polymer is more complete and faster when using a two step process.
• the final polyol mixture for use in the present invention has an average functionality of 1.5 to 8, preferably 2 to 3.
• the hydroxyl number is generally between 200 and 550 mg KOH/g polyol.
• the molecular weight of the polyesters is generally in the range 200 to 3000, preferably 200 to 1000, most preferably 200 to 800.
• polyester polyol as used herein includes any minor amounts of unreacted polyol remaining after the preparation of the polvester polyol and/or uneste ⁇ fied polyol
• the polyester polyol according to the present invention is used to make polyurethane-based rigid foam
• the polyisocyanates and the mixture of lsocyanate- reactive components are generally mixed in a one-shot method Both high and low-pressure techniques can be employed in the mixing step
• the ratio of the NCO/OH groups generally falls within the range 0 85 to 1 40, preferably 0 95 to 1 2 for polyurethane foam, and within the range 50 to 1, preferably 8 to 1 for polyisocyanurate foam
• PEN based polyester polyol of the present invention other isocyanate-reactive compounds can be used in the process for making rigid polyurethane or urethane-modified polyisocyanurate foams Suitable isocyanate-reactive compounds include any of that known in the art for the production of rigid polyurethane foam, especially polyether polyols and other types of polyester polyols
• the PEN based polyester polyol of the present invention constitutes between 60 and 100 % by weight of total isocyanate-reactive compounds
• the isocyanate-reactive mixture generally contains the polyhydric alcohols and other optional additives such as blowing agents, fire retardants. fillers, stabilizers, catalysts and surfactants
• Preferred catalysts for the polyurethane formation are amines, most preferably tertiary amines Dibutyl tm dilaurate is an example of a non-amine based polyurethane catalyst
• Preferred polyisocyanurate catalysts are alkali metal carboxylates and quaternary ammonium carboxylates
• blowing agents known in the art for the preparation of rigid polyurethane or urethane-modified polyisocyanurate foams can be used m the process of the present invention Both physical and chemical blowing agents can be used, singly or in mixtures Suitable physical blowing agents are.
• blowing agents are isomers of pentane such as cyclopentane, n-pentane and isopentane, and mixtures thereof, 1 , 1 -d ⁇ chloro-2-fluoroethane (HCFC 141b), l,l,l-tr ⁇ fluoro-2-fluoroethane (HFC 134a), chlorodifluoromethane (HCFC 22), l,l-d ⁇ fluoro-3,3,3- trifluoropropane (HFC 245fa)
• Carbon dioxide releasing pioducts can be used as chemical blowing agent Water, which releases carbon dioxide upon reaction with isocyanate, is widely known as a chemical blowing agent
• the total quantity of blowing agent is typically from 0 1 to 25% by weight based on the total reaction system
• aromatic polyisocyanates such as diphenylmethane diisocyanate (MDI) and toluene diisocyanate (TDI) or prepolvmers thereof Mixtures of isomers and o gomers can be employed Most preferred is the polymeric form of MDI
• the polyisocvanate can be uretonimine or carbodnmide modified
• the invention is illustrated by, but not limited to. the following examples.
• Example 1-3 Synthesis of the polyester.
• Rigid urethane-modified polyisocyanurate foams were prepared from the polyesters made according to examples 1 to 3 above.
• the formulation components 400 gram
• HCFC 141b was used as blowing agent.
• Ingredients (amounts in parts by weight) and foam physical properties obtained with polyols A, B and C and a comparative example based on a PET polyol are listed in Table 2.
• PET polyol polyester polyol based on scrap PET, OH value 350 mg KOH/gram.
• Tegostab B 8406 silicone based surfactant available from Goldschmidt.
• TEP triethylphosphate fire retardant.
• DMEA dimethylethanolamine catalyst
• Niax A 1 bis(dimethylamino ethylether) catalyst.
• Dabco K15 potassium octoate catalyst.
• SUPRASEC 2085 polymeric MDI available from Huntsman Polyurethanes (SUPRASEC is a trademark of Huntsman ICI Chemicals LLC).
• CT cream time, which is the time from mixing to the change of appearance of the mixed chemicals, which indicates the onset of the expansion.
• ST string time, which is the time from mixing to the instant at which it is possible to pull a string of polymer from the reacting mixture using a spatula.
• ER end-of-rise time, which is the time from mixing to the end of expansion of the foam.
• TF tack-free time which is the time from mixing to when the surface of the foam no longer sticks to a spatula when light pressure is applied.
• Thermal conductivity was measured according to standard ISO 2581. Compression strength was measured according to standard DIN 53421.
• NBS Smoke values were determined according to standard ASTM E 662.
• Rigid urethane-modified polyisocyanurate foams were prepared from the polyesters made according to examples 1 to 3 above.
• the formulation components 400 gram
• Isopentane was used as blowing agent.
• Ingredients (amounts in parts by weight) and foam physical properties obtained using polyols A, B and C and a comparative PET based polyol are listed in Table 3. Table 2

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Polyurethanes Or Polyureas (AREA)
• Polyesters Or Polycarbonates (AREA)

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• 1999
  • 1999-10-07 CA CA002346806A patent/CA2346806A1/en not_active Abandoned
  • 1999-10-07 CN CN99812856A patent/CN1328583A/zh active Pending
  • 1999-10-07 EP EP99950662A patent/EP1131367A1/de not_active Withdrawn
  • 1999-10-07 WO PCT/EP1999/007520 patent/WO2000027899A1/en not_active Application Discontinuation
  • 1999-10-07 JP JP2000581075A patent/JP2002529558A/ja not_active Withdrawn
  • 1999-10-07 AU AU63354/99A patent/AU6335499A/en not_active Abandoned

Non-Patent Citations (1)

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