EP2723794A1

EP2723794A1 - Novel polymers and polymer compositions

Info

Publication number: EP2723794A1
Application number: EP12735662.4A
Authority: EP
Inventors: Alexander Maslow; Alexander Schoolen; Erik Alexander Bijpost
Original assignee: Holland Novochem Technical Coatings BV
Current assignee: Holland Novochem Technical Coatings BV
Priority date: 2011-06-23
Filing date: 2012-06-25
Publication date: 2014-04-30
Also published as: NL1039697A; NL1038882C2; CN103764711B; NL1039697C2; CN103764711A; WO2012177120A1

Abstract

A composition to protect surfaces, such as steel, carbon steel, stainless steel, polyethylenes, polypropylenes, polyacrylates, polyesters, wood, aluminum, ceramics and glass, very efficiently and long lasting, comprising epoxy-containing resins or epoxidized alkene compounds and a curing agent comprising Alkylated polyamine (A) and substituted phenol (B).

Description

Novel Polymers and Polymer Compositions

Introduction

There is a growing demand for new polymers to be applied in, for example, coatings, conductors, membranes. Very often epoxides, especially glycidylether functionalized prepolymers, are used as starting material. They can react with a

nucleophile, such as amines, esters, carboxylic acid,

anhydrides, amides, amidoamines, leading to wide variety of polymers in respect to their physical and chemical properties . These reactions are well described in the literature.

Though widely applied, each epoxy-based curing system possesses its specific drawbacks, such as:

• Limited heat resistance (> 70 °C) , leading to

discoloration and yellowing, and eventually decomposition of the polymer.

• Relatively sensitive for small stoichiometric

deviation, leading to undesired properties (i.e. loss of adhesion, to brittle or to soft polymer and loss of chemical resistance.)

· UV- stability is limited for aromatic epoxides or

their (aromatic) curing agents.

These problems are well-known to those skilled-in-the- arts. Many people have attempted to resolve these problems, i.e. by using combination of curing systems, additives or hybridization, but with limited success, either technically or commercially. Other types of polymers show similar drawbacks.

Objective It is clear that there is a market demand for new

polymers. They should preferably meet the following criteria, but not exclusively:

• Simple and robust system Less susceptible to undesired physical and mechanical properties due to stoichiometric deviations between epoxy and curing agent

Good adhesion to a wide range of substrates High temperature stability

Chemically resistant

UV-stability

Low leachability in a wide range of solvents

Preferably tuneable system:

o Flexibility

o Curing time

o Cross- linking density

o Impact resistance

o Toughness

o Strength

Preferably bio-based raw materials

Affordable products

Suitable as coating system

Safe in use

Invention:

Surprisingly, Applicant found whilst attempting to liquefy cocopropylene diamine for use at room temperature by addition of salicylic acid that at high concentrations up to 40% (w/w) , cocopropylene diamine remains liquid at room and even lower temperatures. Other alkyl (poly) amines have been found to be liquefied by substituted phenols as well. This invention has further been described in an independent patent, which is filed parallel to the patent in the present case.

By thoroughly mixing the cocopropylene diamine/salicylic acid composition with an epoxy resin, followed by curing either at room temperature (<48 hours) or at elevated

temperatures (80 °C, <3 hours) , excellent high gloss

transparent tough polymer films coatings could be obtained. DSC analysis demonstrates no evidence of a T_gi_ass up to at least 250 °C. Physically the polymer films did show neither a significant discoloration nor decomposition. Other epoxy-containing resins, including cycloaliphatics , aliphatics (branched, linear, i.e. Heloxy TP = branched aliphatic) phenolics, Novolac epoxies, end-capped epoxides, epoxidized alkenes, hybrid epoxies, epoxidized cardanol resins/epoxidized cashew nut shell liquid, epoxidized

polyalkenes and epoxidized polyalkadienes can be cured with the alkyl (poly) amine-substituted phenol curing agents as well, leading to a wide range of properties meeting several requirements of the current market demands .

To fulfil specific client criteria, one can add alkene- substituted aromatic hydrocarbons, polydimethylsiloxane derivatives, such as polyester-modified PDMS, reactive

solvents, water scavengers, filling agents, pigments or mixtures thereof as well.

The pot life (the time from combining the components of the coating to the point at which the mixed coating is either no longer usable or the viscosity has doubled from the

starting point) of compositions with alkylpropylene

diamine/salicylic acid and an Epikote 828 epoxy resin can be increased by increasing the amount of salicylic acid (= small excess at stoichiometric ratio) . Another option is to add small amounts ( <5 % by weight based on amount of alkylpropylene diamine/salicylic acid) of another weaker organic acid, such as alkylphosphate esters, or C10-C20 linear or branched carboxylic acid. The curing time can increase at room

temperature, whereas no differences are observed at higher curing temperatures. The resulting polymer layers showed no significant differences with the non- inhibited composition.

Acceleration of epoxy curing can be obtained by addition of small amounts ( < 5% by weight based on amount of

alkylpropylene diamine/salicylic acid) compounds with a greater acidity than salicylic acid, e.g. aromatic sulphonic acids, such as dodecylbenzene sulphonic acid. Description:

Alkylated (poly) amines , (e.g. Duomeen CD (Akzo Nobel), Triameen C (Akzo Nobel) and Tetrameen C (Akzo Nobel) ) have excellent uses like surface active compounds i.e. curing agents, dispersing agents, anti-corrosion film formers and flotation agents. The drawback for the group of fatty amines described above, is that they have the tendency to be solid or crystallize at/or below the most desirable operating

temperature (<<20 °C) .

The most common way of solving this drawback, is to operate on elevated temperatures (>>20 °C) , which in many cases is impossible or impractical. For example, water

temperature cannot be raised in some application or

application of coating on a surface where the temperature is difficult to maintain on the desired level.

Another common solution would be using solvents, which could assist in eliminating at least some of the drawbacks, yet solvent use is under constant pressure of regulation (s) . In this case it would make no difference if the solvent would be on a renewable or non-renewable base. Any emission of solvent into the environment would eventually become under (local or international) regulation (s) .

Over the years, several improvements have been made towards epoxy-based systems for specific applications. For example, US2010/0308477 describes an epoxy resin composition, including curing agent, imidazole and linear saturated

carboxylic acid to establish semiconductor incapsulation .

WO2010/099281 claims high mechanical strength over a wide temperature range with products, comprising epoxy resin composition, comprising linear alkylamine, cyclic aliphatic amine and filler.

US 2,703,765 claims that small amounts of substituted benzoic acids, such as salicylic acid, can act as curing agent for both epoxy- and amine-aldehyde resins. Curing agents comprising epoxies, amines and salicylic acid catalyst are known to those-skilled-in- the arts (e.g. GB 1 362 480 or DE 29 51 603) . However, salicylic acid and the like are never used in high (-stoichiometric) amounts and have never been

published as curing agent in liquid form.

The invention more specifically relates to a composition to protect surfaces, such as steel, carbon steel, stainless steel, polyethylenes , polypropylenes , polyacrylates , polyesters, wood, aluminium, ceramics and glass, very

efficiently and long lasting, comprising

• 5-95% by weight of epoxy- containing resins or epoxidized alkene compounds, and

· 5-95% by weight of curing agent comprising

• 40-99% by weight of alkylated polyamine (A)

and 1-60% by weight of substituted phenol

B

The composition further comprises preferably

• Alkene -substituted aromatic hydrocarbons

• Polydimethylsiloxane derivatives, such as polyester modified PDMS

• Reactive solvents

• Water scavengers

• Filling agents

• Or mixtures thereof

The epoxy resin can be a cycloaliphatic epoxy, phenolic epoxy, Novolac epoxy, end- capped epoxy, epoxidized cardanol resin/epoxidized cashew nut shell liquid or mixtures thereof, and is specifically an epoxidized organosilane or siloxane, silicon epoxy resins or mixtures thereof.

The epoxidized alkene is preferably epoxidized

unsaturated natural oil or its corresponding fatty acids or mixtures thereof, and is in a preferred embodiment a

epoxidized polydiene oligomer or epoxidized polydiene polymer Group R in said alkylated (poly) amine (A) is preferably a linear or branched C1-C24 alkyl or alkylaryl chain, and more preferably R = C6-C18 linear alkyl chain, and still more preferably R = C8-C14 linear alkyl chain.

In the present composition is n preferably 0 - 10.

The amino groups in said alkylated polyamine (A) are preferably connected via linear alkyl ((CH₂)_m), branched alkyl ((CH₂ ) m) , alkylaryl ( (CH₂) _m (aryl) , poly(aryl), alkylene or poly (alkylene) groups; the amino groups are in an embodiment connected via linear alkyl ((CH₂)_m) with m = 1 - 10, and preferably are the amino groups connected via a propylene group ( (CH₂) ₃) ·

According to a preferred embodiment is the alkylated polyamine (A) dodecylpropylenediamine .

The composition according to the invention comprises a substituted phenol ( B ) wherein:

• X = COOH, carboxylate, OH, NH₂, N0₂, S0₃H, COOR, CI,

Br, F, I, alkyl, alkenyl, ether, ketone (COR) or aldehyde

(CHO) ;

· Y = H, COOH, carboxylate, OH, NH₂, N0₂, S0₃H, COOR,

CI, Br, F, I, alkyl, alkenyl, ether, ketone (COR) or aldehyde (CHO) .

More specifically, X = COOH, carboxylate, or OH and Y = H, COOH, carboxylate, OH, NH₂, N0₂, S0₃H, COOR, CI, Br, F, I, alkyl, alkenyl, ether, ketone (COR) or aldehyde (CHO) .

Said substituted phenol ( B ) is preferably catechol or salicylic acid, and more preferably salicylic acid.

The pot life (the time from combining the components of the coating to the point at which the mixed coating is no longer usable) of compositions with alkylpropylene

diamine/salicylic acid and an Epikote 828 epoxy resin can be increased by increasing the amount of salicylic acid (= small excess at stoichiometric ratio, pKa = 2.7). Another option is to add small amounts (<5% by weight based on amount of

alkylpropylene diamine/salicylic acid) of another weaker organic acid (pKa > 2.7), such as alkylphosphate esters, orC10-C20 linear or branched carboxylic acid. The curing time can increase at room temperature, whereas no differences are observed at higher curing temperatures . The resulting polymer layers showed no significant differences with the non- inhibited composition.

Acceleration of epoxy curing can be obtained by addition of small amounts (<5% by weight based on amount of

alkylpropylene diamine/salicylic acid) compounds with a greater acidity than salicylic acid (= acidity < 2.7), e.g. aromatic sulphonic acids, such as dodecylbenzene sulphonic acid.

It has been found that the substituted phenol (B) can at least partially be replaced by a hydroxylated thiophene, hydroxylated pyridine, hydroxylated pyrrole, hydroxylated furan, hydroxylated polycyclic hydrocarbon or hydroxylated substituted polycyclic hydrocarbon compound.

Such a hydroxylated thiophene, hydroxylated pyridine, hydroxylated pyrrole, hydroxylated furan, hydroxylated

polycyclic hydrocarbon or hydroxylated substituted polycyclic hydrocarbon may further comprise a carboxylic acid or

carboxylate group .

The composition according to the invention may further comprise colouring agents, in particular pigments, or filling agents, especially nanoparticles or modified nanoparticles , in particular silicium dioxide nanoparticles.

The invention also relates to a method for curing the present composition by heating the curing system to a

temperature and for a sufficient time, which is preferably performed at a temperature lower than 130 °C, more

specifically between room temperature and 80 °C.

Experimental/Examples

The invention will be illustrated by a number of

examples, but this is not intended to limit the scope of the invention. Many modifications and variations can be made without departing from its spirit and scope, as will be apparent to those skilled-in-the-arts .

Typical preparation of the curing agent

Cocopropylene diamine (Duomeen CD - Akzo Nobel Surface Chemistry) is molten at 40 °C. 50 grams Duomeen CD is transferred into a glass beaker, equipped with a magnetic stirring bar, followed by slow addition of 27 grams salicylic acid (1 : 1 molar ratio) . Stirring is continued till a clear light yellow solution is obtained.

Typical coating preparation and performance tests

The protective layers have been prepared as follows. The starting materials have been thoroughly mixed in a 50 ml.

glass vessel. Afterwards the mixture is applied on a carbon steel Q-panel (60 micron layer) and an aluminium surface (350 micron layer) . The treated surfaces are allowed to cure at 80- 90 °C. The obtained materials are subjected to scratch tests, adhesive strength and flexibility, chemical resistance (strong acidic, alkaline and salt media) and Differential Scanning Calorimetry (DSC) .

Table 1: Compositions of protective layers

Table 2: Results of coating performance tests on carbon steel panels

Table 3: Results of coating performance tests on aluminium surfaces

Claims

1. A composition to protect surfaces, such as steel, carbon steel, stainless steel, polyethylenes , polypropylenes , polyacrylates , polyesters, wood, aluminium, ceramics and glass, very efficiently and long lasting, comprising

• 5-95% by weight of epoxy-containing resins or epoxidized alkene compounds, and

• 5-95% by weight of curing agent comprising

• 40-99% by weight of alkylated polyamine (A)

and 1-60% by weight of substituted phenol

B

2. Composition according to claim 1 further comprising a compound selected from the group, consisting of:

• Alkene-substituted aromatic hydrocarbons,

• Polydimethylsiloxane derivatives, such as polyester- modified PDMS,

• Reactive solvents,

• Water scavengers,

• Filling agents,

• Or a mixture thereof .

3. Composition according to Claim 1 or 2 , wherein the epoxy resin is a cycloaliphatic epoxy, phenolic epoxy, Novolac epoxy, end-capped epoxy, epoxidized cardanol resin/epoxidized cashew nut shell liquid or mixtures thereof.

4. Composition according to one or more of the claims 1-3, wherein the epoxy resin is an epoxidized organosilane or siloxane, silicon epoxy resins or mixtures thereof.

5. Composition according to one or more of the claims 1-4, wherein the epoxidized alkene is epoxidized unsaturated natural oil or its corresponding fatty acids or mixtures thereof .

6. Composition according to one or more of the claims 1-4, wherein the epoxidized alkene is epoxidized polydiene oligomer or epoxidized polydiene polymer.

7. Composition according to one or more of the claims 1-6, wherein group R in said alkylated (poly) amine (A) is a linear or branched C1-C24 alkyl or alkylaryl chain.

8. Composition according to claim 7, wherein R = C6-C18 linear alkyl chain.

9. Composition according to claim 7 or 8, wherein R = C8-C14 linear alkyl chain.

10. Composition according to one or more of the claims 1-9, wherein n = 0 - 10

11. Composition according to one or more of the claims 1-10, wherein the amino groups in said alkylated polyamine (A) are connected via linear alkyl ((CH₂)_m), branched alkyl ((CH₂)_m)/ alkylaryl ( (CH₂) _m (aryl) , poly(aryl), alkylene or poly (alkylene) groups .

12. Composition according to claim 11, wherein the amino groups are connected via linear alkyl ((CH₂)_m) with m = 1 - 10.

13. Composition according to claim 11 or 12, wherein the amino groups are connected via a propylene group ((CH₂ ) 3 ) .

14. Composition according to one or more of the claims 1-13, wherein the alkylated polyamine (A) is

dodecylpropylenediamine .

15. Composition according to one or more of the claims 1-13, wherein the alkylated polyamine (A) is the corresponding polymer of (A) .

16. Composition according to one or more of the claims 1-15, wherein in said substituted phenol (B) :

· X = COOH, carboxylate, OH, NH₂, N0₂, S0₃H, COOR, CI,

Br, F, I, alkyl, alkenyl, ether, ketone (COR) or aldehyde (CHO) ;

• Y = H, COOH, carboxylate, OH, NH₂, N0₂, S0₃H, COOR, CI, Br, F, I, alkyl, alkenyl, ether, ketone (COR) or aldehyde (CHO) .

17. Composition according to claim 16, wherein X = COOH, carboxylate, or OH and Y = H, COOH, carboxylate, OH, NH₂ , N0₂ , S0₃H, COOR, CI, Br, F, I, alkyl, alkenyl, ether, ketone (COR) or aldehyde (CHO) .

18. Composition according to one or more of the claims 1-17, wherein said substituted phenol (B) is catechol or salicylic acid.

19. Composition according to claim 18, wherein said

substituted phenol (B) is salicylic acid.

20. Composition according to one or more of the claims 1 - 19, wherein the pot life of said composition can be increased by addition of an acidic compound with pKa > 2.7.

21. Composition according to one or more of the claims 1 - 20, wherein the pot life of said composition can be decreased by- addition of an acidic compound with pKa < 2.7.

22. Composition according to one or more of the claims 1 - 21, wherein the substituted phenol (B) is at least partially replaced by a hydroxylated thiophene, hydroxylated pyridine, hydroxylated pyrrole, hydroxylated furan, hydroxylated

polycyclic hydrocarbon or hydroxylated substituted polycyclic hydrocarbon compound.

23. Composition according to claim 22, wherein said

hydroxylated thiophene, hydroxylated pyridine, hydroxylated pyrrole, hydroxylated furan, hydroxylated polycyclic

hydrocarbon or hydroxylated substituted polycyclic hydrocarbon further comprises a carboxylic acid or carboxylate group.

24. Composition according to one or more of the claims 1-23, further comprising colouring agents, in particular pigments.

25. Composition according to one or more of the claims 1-24 further comprising filling agents, especially nanoparticles or modified nanoparticles, in particular silicium dioxide

nanoparticles .

26. Method for curing the composition according to one or more of the claims 1-25, by heating the curing system to a

temperature and for a sufficient time.

27. Method according to claim 26, wherein the curing is performed at a temperature lower than 130 °C.

28. Method according to claim 26 or 27, wherein the curing is performed between room temperature and 80 °C.