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CN-117616009-B - Aromatic carbodiimide, method for producing same and use thereof

CN117616009BCN 117616009 BCN117616009 BCN 117616009BCN-117616009-B

Abstract

The present invention relates to novel carbodiimides, to a process for their production, and to the use of the novel carbodiimides as stabilizers in ester-based polyols, in polyethylene terephthalate (PET), in polybutylene terephthalate (PBT), in polytrimethylene terephthalate (PTT), in copolyesters, in Thermoplastic Polyester Elastomers (TPE), in Ethylene Vinyl Acetate (EVA), in polylactic acid (PLA) and/or in PLA derivatives, in polybutylene terephthalate adipate (PBAT), in polybutylene succinate (PBS), in Polyhydroxyalkanoates (PHA), in blends, in triglycerides, in thermoplastic polyurethanes, in polyurethane elastomers, in PU adhesives, in PU casting resins, in PU coatings or in PU foams.

Inventors

  • LAUFER WILHELM

Assignees

  • 朗盛德国有限责任公司

Dates

Publication Date
20260508
Application Date
20220708
Priority Date
20210714

Claims (20)

  1. 1. Carbodiimide of formula (I) Wherein the method comprises the steps of R may be the same or different and is selected from the group consisting of-NCN-R I -and-NHCOOR III , where R I represents C 1 -C 22 -alkyl, C 6 -C 12 -cycloalkyl, C 6 -C 18 -aryl or C 6 -C 18 -aralkyl, and R III represents an alkylated polyoxyalkylene group, R 1 、R 2 and R 3 each independently of one another represent methyl, isopropyl or n-propyl, where on each benzene ring one of the radicals R 1 、R 2 and R 3 is methyl, and N is from 0 to 500.
  2. 2. The carbodiimide of claim 1 wherein R I represents triisopropylphenyl.
  3. 3. The carbodiimide of claim 1 wherein n is from 1 to 50.
  4. 4. A carbodiimide according to claim 1 wherein R 1 、R 2 and R 3 each independently of the other represent methyl-or isopropyl-.
  5. 5. The carbodiimide according to any one of claims 1-4, wherein the carbodiimide content is 2% -17% by weight.
  6. 6. The carbodiimide according to any one of claims 1 to 4, wherein in formula (I), R represents NCN-R I , n is from 0 to 500.
  7. 7. The carbodiimide of claim 6 wherein n is from 1 to 100.
  8. 8. The carbodiimide of claim 6 wherein n is from 1 to 50.
  9. 9. The carbodiimide of claim 6 wherein the carbodiimide content is 10% -17% by weight.
  10. 10. The carbodiimide of claim 6 wherein the carbodiimide content is 11% -15% by weight.
  11. 11. The carbodiimide of claim 6 wherein the carbodiimide content is 13% -14% by weight.
  12. 12. The carbodiimide according to any one of claims 1 to 4, wherein in formula (I), R represents-NHCOOR III , n is from 0 to 20.
  13. 13. The carbodiimide of claim 12 wherein n is from 1 to 10.
  14. 14. The carbodiimide of claim 12 wherein n is from 3 to 8.
  15. 15. The carbodiimide according to claim 12, wherein the carbodiimide content is from 4 to 13% by weight.
  16. 16. The carbodiimide according to claim 12, wherein the carbodiimide content is from 10 to 13% by weight.
  17. 17. The carbodiimide according to any one of claims 1 to 4 wherein in formula (I), R represents-NHCOOR III and R III represents an alkylated polyoxyalkylene group, n being from 0 to 20.
  18. 18. The carbodiimide of claim 17 wherein n is from 1 to 10.
  19. 19. The carbodiimide of claim 17 wherein n is from 1 to 4.
  20. 20. The carbodiimide of claim 17 wherein n is from 2 to 3.

Description

Aromatic carbodiimide, method for producing same and use thereof Background Carbodiimides have proven advantageous in many applications, for example as hydrolysis inhibitors for thermoplastics, polyols, polyurethanes, triglycerides and lubricating oils. For this purpose, highly sterically hindered polycarbodiimides are preferably used, although these polycarbodiimides are produced from very special raw materials and are therefore very expensive to procure. Furthermore, highly sterically hindered carbodiimides, such as those based on triisopropylphenyl isocyanate, have a very high melting point, are insoluble and can be incorporated into the starting materials of the polyurethanes only with considerable effort and equipment investment if possible. Aromatic carbodiimides based on cheaper raw materials, such as those described in EP 2997010 B1, can achieve very good hydrolysis inhibition in some ester-based polymers such as PET or PLA, but in other applications, such as in polyurethanes, these aromatic carbodiimides have the disadvantage of not sufficiently inhibiting hydrolysis and thus cannot be used universally. The carbodiimides of the prior art are generally in a form which is difficult to meter, in particular in the form of adhesive compositions. Thus, there is a need for new carbodiimides which do not exhibit the disadvantages of the prior art, are easy to produce, exhibit high thermal stability, also achieve excellent hydrolysis inhibition in polyurethane applications and are additionally easier to meter. Disclosure of Invention This object is surprisingly achieved by carbodiimides of the formula (I) Wherein the method comprises the steps of R may be the same or different and is selected from the group consisting of-NCN-R I and-NHCOOR III, wherein R I represents C 1-C22 -alkyl, C 6-C12 -cycloalkyl, C 6-C18 -aryl or C 6-C18 -aralkyl, preferably triisopropylphenyl, and R III represents an alkylated polyoxyalkylene (polyoxyalkylene) group, R 1、R2 and R 3 each independently of one another represent methyl, isopropyl or n-propyl, where on each benzene ring one of the radicals R 1、R2 and R 3 is methyl, and N is from 0 to 500, preferably n is from 1 to 50. The molar mass of the alkylated polyoxyalkylene groups is preferably at least 200g/mol, particularly preferably from 200g/mol to 600g/mol and most preferably from 350g/mol to 550g/mol. The carbodiimide content (NCN content, measured by titration with oxalic acid) of the carbodiimide according to the invention is generally 2% -17% by weight. To determine the NCN content, the NCN groups were reacted with an excess of added oxalic acid, and then unreacted oxalic acid was subjected to potential back titration with sodium methoxide, taking into account the blank value of the system. Preference is given to carbodiimides, where R 1、R2 and R 3 each independently of one another represent methyl or isopropyl-. Preference is given to carbodiimides of the formula (I), wherein R denotes NCN-R I, wherein n is from 0 to 500, preferably from 1 to 100 and most preferably from 1 to 50, and the carbodiimide content is preferably from 10% to 17% by weight, particularly preferably from 11% to 15% by weight and most preferably from 13% to 14% by weight. Further preferred embodiments relate to carbodiimides of formula (I), wherein R represents NHCOOR III, wherein n is from 0 to 20, preferably from 1 to 10, particularly preferably from 3 to 8, and the carbodiimide content is preferably from 4% to 13% by weight, particularly preferably from 10% to 13% by weight. The carbodiimide of formula (I) (wherein r= -NCN-R I, wherein R I is as defined above, and R 1、R2 and R 3 each independently represent methyl-or isopropyl-, wherein on each benzene ring one of the groups R 1、R2 and R 3 is methyl) is solid and has a softening point of >40 ℃. They are therefore very suitable for stabilizing ester-based polymers, preferably polymers selected from the group consisting of polyester polyols, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (polytrimethylene terephthalate) (PTT), copolyesters such as cyclohexanediol and the modified polyesters of terephthalic acid (PCTA), thermoplastic polyester elastomers (TPE E), ethylene Vinyl Acetate (EVA), polylactic acid (PLA) and/or PLA derivatives, polybutylene terephthalate adipate (PBAT), polybutylene succinate (PBS), polyhydroxyalkanoates (PHA), polyurethane elastomers (preferably Thermoplastic Polyurethane (TPU)), and blends (preferably PA/PET or PHA/PLA blends). The invention further relates to a method for stabilizing an ester-based polymer by adding the above carbodiimide. The above carbodiimide is preferably added to the ester-based polymer using a solid metering unit. The solid metering units in the context of the present invention are preferably single-screw extruders, twin-screw extruders and multi-screw extruders, continuous co-kneaders (Buss type) and batch kneaders (e.g.banbury type). In a fur