A two-component polyurethane adhesive

Patent metadata

Field	Value
Publication number	US-2020239752-A1
Application number	US-201816755379-A
Country	US
Kind code	A1
Filing date	Oct 16, 2018
Priority date	Oct 17, 2017
Publication date	Jul 30, 2020
Grant date	—

Abstract

Described herein is a two-component polyurethane adhesive that exhibits a glass transition temperature (Tg) of ≥70° C. and an open time in the range of ≥45 to ≤90 minutes at a temperature of ≥70° C. and a relative humidity of 50%. Also described is a method of producing the two-component polyurethane adhesive having a long open time with good humidity tolerance which is suitable for bonding large and bulky components or surfaces, including but not limited to, rotor blades of wind turbines.

First claim

1 . A two-component polyurethane adhesive comprising:
i. at least one polyol component (C1) comprising: a) ≥8 to ≤30 wt. % of at least one polyether polyol (P1) having a functionality of 4; wherein the at least one polyether polyol (P1) is represented by the following formula (I);

wherein R 1 , R 2 , R 3 and R 4 each, identical or different, are selected from the group consisting of —CH 2 —CH 2 —, —CH(CH 3 )—CH 2 —, —CH(C 2 H 5 )—CH 2 —, —C(CH 3 ) 2 —CH 2 — and —CH 2 —CH 2 —CH 2 — and
n each, identical or different, is a real number in a range of ≥1 to ≤6,
b) ≥5 to ≤20 wt. % of at least one polyol containing an aromatic moiety (P2), and
c) ≥20 to ≤70 wt. % of at least one polyol derived from a natural oil polyol (P3), whereby the weight percentages relate in each case to an overall amount of the at least one polyol component (C1); and
ii. at least one aromatic polyisocyanate;
whereby the two-component polyurethane adhesive exhibits a glass transition temperature of ≥70° C., the glass transition temperature being determined by a DSC measurement according to DIN 11357 at a heating rate of 20° C./min.

2 . The two-component polyurethane adhesive according to claim 1 , wherein R 1 , R 2 , R 3 and R 4 each, identical or different, are selected from the group consisting of —CH 2 —CH 2 — and —CH(CH 3 )—CH 2 —.

3 . The two-component polyurethane adhesive according to claim 1 , wherein n each, identical or different, is a real number in a range of ≥1 to ≤4.

4 . The two-component polyurethane adhesive according to claim 1 , wherein the at least one polyether polyol (P1) has a hydroxyl number in a range of ≥150 to ≤700 mg KOH/g.

5 . The two-component polyurethane adhesive according to claim 1 , wherein the at least one polyol component (C1) comprises ≥10 to ≤25 wt. % of the at least one polyether polyol (P1), whereby the weight percentage relates to the overall amount of the at least one polyol component (C1).

6 . The two-component polyurethane adhesive according to claim 1 , wherein the at least one polyol containing an aromatic moiety (P2) has a hydroxyl number in a range of ≥130 to ≤340 mg KOH/g.

7 . The two-component polyurethane adhesive according claim 1 , wherein the at least one polyol component (C1) comprises ≥5 to ≤15 wt. % of the at least one polyol containing an aromatic moiety (P2), whereby the weight percentage relates to the overall amount of the at least one polyol component (C1).

8 . The two-component polyurethane adhesive according to claim 1 , wherein the aromatic moiety is bisphenol.

9 . The two-component polyurethane adhesive according to claim 1 , wherein the at least one polyol derived from a natural oil polyol (P3) has a hydroxyl number in a range of ≥150 to ≤250 mg KOH/g.

10 . The two-component polyurethane adhesive according to claim 1 , wherein the at least one polyol component (C1) comprises ≥25 to ≤60 wt. % of the at least one polyol derived from a natural oil polyol (P3), whereby the weight percentage relates to the overall amount of the at least one polyol component (C1).

11 . The two-component polyurethane adhesive according to claim 1 , wherein the natural oil polyol is selected from the group consisting of castor oil and natural oil polyols derived from soybean oil, rapeseed oil, coconut oil, peanut oil, palm oil, sunflower oil, olive oil or canola oil.

12 . The two-component polyurethane adhesive according to claim 1 , wherein the at least one polyol derived from a natural oil polyol (P3) is an alkoxylation product of the natural oil polyol.

13 . The two-component polyurethane adhesive according to claim 1 , wherein the natural oil polyol is castor oil.

14 . The two-component polyurethane adhesive according to claim 1 , wherein the at least one polyol component (C1) comprises ≥10 to ≤25 wt. % of the at least one polyether polyol (P1), ≥5 to ≤15 wt. % of the at least one polyol containing an aromatic moiety (P2) ≥25 to ≤60 wt. % of the at least one polyol derived from a natural oil polyol (P3), and ≥10 to ≤40 wt. % of at least one additive selected from the group consisting of chain extenders, water scavengers, fillers, deaerating agents, thixotropic agents, antioxidants, dyes, catalysts, desiccants, resins, plasticizers, wetting agents and pigments, whereby the weight percentages relate to the overall amount of the at least one polyol component (C1).

15 . The two-component polyurethane adhesive according to claim 1 , wherein the aromatic polyisocyanate further comprises at least one deactivator.

16 . The two-component polyurethane adhesive according to claim 15 , wherein the at least one deactivator is selected from the group consisting of an aliphatic and an aromatic acid chloride selected from the group consisting of acetyl chloride, benzoyl chloride, benzene sulfonyl chloride, oxalyl chloride, adipyl chloride, sebacyl chloride and carbonyl chloride; an inorganic acid selected from the group consisting of perchloric acid; an organic acid selected from the group consisting of trifluoromethane sulfonic acid and trifluoroacetic acid; and a chloroformate selected from the group consisting of methyl chloroformate, ethyl chloroformate, isopropyl chloroformate, n-butyl chloroformate, sec-butyl chloroformate and diethylene glycol bischloroformate.

17 . The two-component polyurethane adhesive according to claim 1 , wherein the aromatic polyisocyanate is selected from the group consisting of polymeric methylene diphenyl diisocyanate and polymeric toluene diisocyanate.

18 . The two-component polyurethane adhesive according to claim 1 , wherein the two-component adhesive comprises ≥0.05 to ≤1.0 wt. % of at least one heat activated catalyst, whereby the weight percentage relates to the overall amount of the at least one polyol component (C1).

19 . The two-component polyurethane adhesive according to claim 18 , wherein the at least one heat activated catalyst is a cyclic tertiary amine.

20 . The two-component polyurethane adhesive according to claim 19 , wherein the cyclic tertiary amine is selected from the group consisting of 1,8-diaza-bicyclo[5.4.0]undec-7-ene,1,5-diaza-bicyclo[4.3.0 ]non-5-ene, 1,4 diazabicyclo[2.2.2]octane, N-cetyl-N,N-dimethylamine and dimethyl cyclohexylamine.

21 . The two-component polyurethane adhesive according to claim 20 , wherein the cyclic tertiary amine is blocked 1,8-diaza-bicyclo[5.4.0]undec-7-ene.

22 . The two-component polyurethane adhesive according to claim 1 , wherein the two-component polyurethane adhesive comprises ≥10 to ≤40 wt. % of at least one additive, whereby the weight percentage relates to the overall amount of the at least one polyol component (C1).

23 . The two-component polyurethane adhesive according to claim 22 , wherein the at least one additive is selected from the group consisting of chain extenders, water scavengers, fillers, deaerating agents, thixotropic agents, antioxidants, dyes, catalysts, desiccants, resins, plasticizers, wetting agents and pigments.

24 . The two-component polyurethane adhesive according to claim 1 , wherein the glass transition temperature is in a range of ≥70 to ≤90° C., the glass transition temperature being determined by the DSC measurement according to DIN 11357 at the heating rate of 20° C./min.

25 . A method for producing the two-component

Assignees

• Basf Se

Inventors

• Kaffee Achim

Classifications

• Y02E10/72

  Wind turbines with rotation axis in wind direction · CPC title

• C08G18/12

  using two or more compounds having active hydrogen in the first polymerisation step · CPC title

• C08G18/7657

  containing two or more aromatic rings · CPC title

• C08G18/4891

  modified with higher fatty oils or their acids or by resin acids · CPC title

• F03D1/0675

  of the blades · CPC title