Patent Application
20150031813
The present invention is directed to compositions of green coalescents comprising monoesters obtained from direct or indirect esterification of vegetable oil fatty acids and fusel oil alcohols. Fatty acids used in the present invention have 6 to 22 carbon atoms and can be either saturated or unsaturated.
Coalescing agents are generally used in paints, varnishes and water-based adhesives. Coalescing agents act as a solvent and/or a plasticizer to the polymeric phase of paints, varnishes and adhesive formulations, diminishing the Tg thereof and favoring the formation of continuous and homogeneous films at several temperature and humidity conditions. Coalescing agents need to be stable in the presence of water and compatible with ingredients present in paints, varnishes and adhesive formulations. Specially, coalescing agents cannot destabilize polymer particles present in paints, varnishes and adhesive formulations. Coalescing agents should also be sufficiently volatile to be eliminated during drying of films, preferably after water evaporation.
The plasticization power of a coalescing agent, that is, the ability thereof in diminishing Tg of a polymer, depends on solubility parameters of the coalescent and the polymer. Usually, water-insoluble coalescing agents having solubility parameters that are compatible with those of the polymer to be plasticized are more effective in reducing MFFT than water-soluble coalescing agents.
Currently, there is an increasing need for coalescing agents that meet the environmental legislation that controls emission of volatile organic compounds (VOC) to the atmosphere. According to European Directive legislation 2004/42/CE coalescing agents having a boiling point of less than 250° C. are considered volatile organic compounds. Other features of coalescing agents that are valuable to manufacturers of paints, adhesives and varnishes and for the final consumer are: low odour, HAP-free, renewable raw material-derived coalescents having high vegetalization index and low CO2 emission during the manufacture process.
Several molecules having alcohol and/or ester functionality are used as a coalescing agent. Butyl glycol (Dow and Oxiteno), 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (Texanol from Eastman Kodak) monoethylene glycol phenyl ether (Dow, Oxiteno) are the molecules most used as coalescents. Due to its boiling point of 169-173° C. butyl glycol is considered a VOC by the European Legislation. Texanol, which has a boiling point of around 254° C. is not considered a VOC by the European Legislation. Nevertheless, Texanol is not derived from renewable raw material.
Patent literature contemplates only a few reports mentioning the use of fusel oil-derived esters as coalescing agents and/or plasticizers.
US patent application US2009/0198002 A1 to Rhodia INC entitled “Low VOC Coalescing Agents”, describes the use of diesters of adipic, glutaric and succinic acids and alcohols comprising a hydrocarbon chain having 4 to 8 carbon atoms, including alcohols from fusel oil. Diesters obtained from glycol ethers and diacids are also encompassed in the invention.
Based on the aforementioned patent example, one notes that the use of fusel oil-derived esters (US2009/0198002 A1) has been little explored. In addition, molecules described by Rhodia in application US2009/0198002 A1 are diesters from diacids and fusel oil. Accordingly, it is evident that monoesters of vegetable oil fatty acids and fusel oil alcohols have not been explored so far.
The present invention relates to the use of green coalescents obtained from an esterification reaction of fusel oil alcohols and vegetable oil fatty acids. Fatty acids used in the present invention have 6 to 22 carbon atoms and can be saturated or unsaturated.
In particular, the present invention provides a composition of green coalescents comprising monoesters obtained from direct or indirect esterification of vegetable oil fatty acids and fusel oil alcohols.
The present invention describes the use of coalescing agents and/or plasticizers comprising monoesters of fusel oil alcohols and vegetable oil fatty acids.
In the present invention, the terms “coalescing agents” and “coalescent” refer to solvents capable of reducing MFFT (minimum film forming temperature), that is, acting as a plasticiser for the polymeric phase.
The coalescing agents listed in the present invention can be used in the formulation of paints, adhesives and varnishes containing latexes or polymer dispersions. Preferably, latexes are selected from: styrene-butyl acrylate, styrene-butyl acrylate-acrylic acid, styrene-butyl acrylate-methacrylic acid, styrene-butadiene, styrene-butadiene-acrylic acid, styrene-butadiene-methacrylic acid, acrylonitrile-butadiene, acrylonitrile-butadiene-acrylic acid, acrylonitrile-butadiene-methacrylic acid, polyacrylates, polyacrylates-acrylic acid, polyacrylates-methacrylic acid, polyacrylates-carboxylic acids in a general manner and polyvinyl acetate.
The coalescing agents mentioned herein can also be used in civil construction, architectural paints, industrial paints, original paints, automotive repaints, paints and varnishes for packages in general.
Preferably, the concentration of fusel oil monoesters and vegetable oil fatty acids in formulations of paints, adhesives and varnishes and latexes can range between 0.1 and 50% in relation to the polymer content present in the formulations or latexes.
Said coalescing agents are preferably suitable for polymeric dispersions in water and formulations containing such dispersions.
Coalescing agents of the present invention are monoesters derived from fusel oil having a boiling point of greater than 250° C.
The ability of coalescing agents in plasticizing polymer particles, that is, in diminishing wet Tg of polymers has been monitored via MFFT assays of latex films comprising 2 mass % of the coalescing agents.
Wet abrasion resistance of coalescing agents-containing paint films has been monitored via washability tests.
Preferably, in the composition in accordance with the invention, alcohols derived from fusel oil have 4 to 5 carbon atoms.
Preferably, in the composition in accordance with the invention, green coalescents are derived from renewable raw material.
The invention will now be described by means of the following examples, which are merely exemplary and should not be construed as a limitation on the scope of the invention.
MFFT results suggest that the fusel oil-derived ester has greater ability in plasticizing polymer particles than the further coalescing agents evaluated.
Boiling points of the coalescing agents of
Washability results obtained for opaque paints described in Table 2 containing the green coalescent, phenyl glycol and Texanol are depicted in
Washability results suggest that opaque paint films containing the green coalescent of the present invention, a fusel oil-derived ester, are more resistant to wet abrasion than opaque paint films containing Texanol and phenyl glycol.
| Number | Date | Country | Kind |
|---|---|---|---|
| PI 1102427-5 | May 2011 | BR | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/BR2012/000141 | 5/16/2012 | WO | 00 | 10/10/2014 |
