NZ616878B2 - Glycerol based unsaturated polyester resins and raw materials therefor - Google Patents

Abstract

Disclosed is a process for the preparation of glycerolacetylesters, in which acetic acid and glycerol having the molar ratio of less than 2.5 are reacted in the presence of a stannous catalyst (e.g. Fascat 4102 / monobutyltin tris(2-ethylhexanoate)) to produce a mixture of glycerol, mono-, di- and triacetylglycerolester. The amount of tri-ester may be less than 15 mol%, the amount of glycerol may be less than 25 mol%, the amount of monoester may be about 20 mol% or more and the amount of diester may be about 20 mol% or more preferred about 40 mol% or more. Also disclosed is an unsaturated polystyrene comprising polyester comprising more than 5 wt% of the glycerolacetylesters obtained by the above process, and copolymerized into the polymer, said polyester also preferably comprises more than 10 mol% of a poly-acid component in the unsaturated polyester, the poly-acid component being a polymerized residue of fumaric or maleic acid. riacetylglycerolester. The amount of tri-ester may be less than 15 mol%, the amount of glycerol may be less than 25 mol%, the amount of monoester may be about 20 mol% or more and the amount of diester may be about 20 mol% or more preferred about 40 mol% or more. Also disclosed is an unsaturated polystyrene comprising polyester comprising more than 5 wt% of the glycerolacetylesters obtained by the above process, and copolymerized into the polymer, said polyester also preferably comprises more than 10 mol% of a poly-acid component in the unsaturated polyester, the poly-acid component being a polymerized residue of fumaric or maleic acid.

Description

GLYCEROL BASED UNSATURATED POLYESTER RESINS AND RAW MATERIALS THEREFOR BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to glycerol based unsaturated polyester resins and raw als therefore. 2. Description of the Related Art Unsaturated polyester resins are commonly used in constructive parts in for example building, automotive and ilding industries.

One of the ns in ry is the reliance on oil based resources. The environment would be aided if use could be made of raw materials of natural resources.

Several studies exist on this subject. For example de Meire/es Brioude et al. in 'Synthesis and Characterization of Aliphatic Polyesters from Glycerol, by-Product of Biodiesel tion, and Adipic Acid'. Materials Research, (2007) 10, 335-339 describe the use of glycerol, a waste product from the tion of biodiesel. Another example by Miyagawa, H. et al. in 'Development of biobased rated polyester ning functionalised linseed oil'. Ind. Eng. Chem. Res, (2006) 45, 1014-1018 bes the use of functionalized linseed oil as an addition material to traditional unsaturated polyester resins. However, the use of functionalized linseed oil causes a decrease in modulus.

There is an ongoing need for unsaturated polyester resins that use bioderivable raw materials.

BRIEF SUMMARY OF THE INVENTION The present invention relates to unsaturated polyester resins comprising a substantial amount of glycerol. Glycerol is a duct from the manufacture of biodiesel, and is nowadays a cheap bioderived raw al. r, because glycerol is tri- functional, its use in polymer systems like unsaturated polyesters for making thermoset products through radical polymerization with high strength and modulus, has been very limited.

The present invention therefore furthermore relates to the use of glycerol mono- and diacetate (hereinafter also denoted as mono/di/tri glycerol esters) in the manufacture of unsaturated polyester resins and other resins.

The present invention furthermore relates to the process of making mono and diacetyl esters of glycerol from acetic acid and glycerol with a relatively low molar ratio while using an organotin catalyst.

The present invention furthermore relates to the process of making an unsaturated polyester from an α,ß-unsaturated carboxylic acid and at least a acetylglycerol esters, wherein mono- and diacetyl esters of glycerol are made from glycerol and acetic acid while using an organotin st, and wherein in making the unsaturated polyester the same organotin catalyst is used.

] The present invention as d herein is described in the following items 1 to 21: 1. A process for the ation of glycerolacetylesters, in which acetic acid and glycerol having the molar ratio of less than 2.5 are reacted in the presence of a us catalyst to produce a mixture of glycerol, mono-, di- and triacetylglycerolester. 2. The process according to item 1, wherein the acetic acid and glycerol have a molar ratio of between about 1.5 and about 2.2. 3. The process according to any one of the preceding items, wherein the resulting amount of triester relative to the resulting amounts of glycerol, monoester and diester is less than 15 mol%. 4. The process ing to any one of the preceding items, wherein the resulting amount of triester relative to the resulting amounts of glycerol, monoester and diester is less than 10 mol%.

. The process according to any one of the preceding items, wherein the resulting amount of ol relative to the resulting amounts of ter, diester and triester is less than 25 mol%. 6. The process according to any one of the preceding items, wherein the resulting amount of glycerol relative to the resulting amounts of monoester, diester and er is less than 15 mol%. 7264538_1 (GHMatters) P95050.NZ JENNYP 7. The process according to any one of the ing items, wherein the resulting amount of mono-ester relative to the resulting amounts of glycerol, r and triester is about 20 mol% or more, and n the resulting amount of mono-ester relative to the resulting amounts of glycerol, diester and triester is about 50 wt% or less. 8. The process according to any one of the preceding items, wherein the resulting amount of mono-ester relative to the resulting amounts of glycerol, diester and triester is about 30 mol% or more, and wherein the resulting amount of mono-ester relative to the resulting amounts of glycerol, r and triester is about 50 wt% or less. 9. The process according to any one of the preceding items, wherein the resulting amount of di-ester relative to the resulting amounts of ol, monoester and triester is about 20 mol% or more, and wherein the resulting amount of di-ester relative to the resulting amounts of glycerol, monoester and er is about 60 wt% or less.

. The process according to any one of the preceding items, wherein the resulting amount of di-ester relative to the resulting amounts of glycerol, monoester and triester is about 40 mol% or more, and wherein the resulting amount of di-ester relative to the resulting amounts of glycerol, monoester and triester is about 60 wt% or less. 11. The process according to any one of the preceding items, wherein the resulting mixture has a hydroxyl value from about 300 to about 700. 12. The process according to any one of the preceding items, wherein the resulting mixture has a hydroxyl value from about 300 to about 550. 13. The process according to any one of the preceding items, wherein the resulting mixture has an acid value of from about 5 to about 60. 14. The process according to any one of the preceding items, wherein the ing amount of triester relative to the resulting amounts of glycerol, ter and diester is r than 1.0 mol%, and wherein the ing amount of glycerol relative to the ing amounts of monoester, diester and triester is about 5 mol% or more.

. A mixture of glycerolacetylesters obtained by the process according to any one of the preceding items. 7264538_1 (GHMatters) P95050.NZ JENNYP 16. The use of a mixture obtained by the process according to any one of items 1-14, or the use of the mixture of item 15, in the preparation of unsaturated ters that can be rized through radical polymerization to form articles. 17. An unsaturated polyester comprising more than 5 wt% of the glycerolacetylesters obtained by the process according to any one of items 1-14, copolymerized in the polymer. 18. The unsaturated polyester according to item 17, wherein the rated polyester comprises more than 10 mol% of a poly-acid ent in the rated polyester, the poly-acid component being a polymerized residue of fumaric or maleic acid. 19. The unsaturated polyester according to any one of items 17-18, wherein the unsaturated polyester comprises polystyrene.

. An unsaturated polyester composition comprising: the unsaturated polyester according to any one of items 17-19; and any one of fibres, fillers and/or catalysts. 21. A process of making an rated polyester by reacting an α,ß-unsaturated carboxylic acid and at least a glycerolacetylester, wherein mono- and diacetylesters of glycerol are made from glycerol and acetic acid using an organotin catalyst, and wherein in making the rated polyester the same organotin catalyst is used.

DETAILED DESCRIPTION OF THE INVENTION In one ment of the invention, the invention relates to a process for making acetylesters of glycerol while using a stannous catalyst, the acetylester mixture being a e of non-reacted, mono-, di-, and/or triacetylglycerolester. This process for making a mixture of acetylesters of glycerol is performed with such an acetic acid / glycerol ratio that the product can be directly used in the unsaturated polyester manufacture. This is for example possible with ratio of acetic acid to glycerol of about 1.5 to 1 or higher, ably 1.7 to 1 or higher. lly, it is preferred to have this ration 2.5 to 1 or lower, preferably 2.2 to 1 or lower. 7410766_1 (GHMatters) P95050.NZ JENNYP The use of a stannous catalyst allows a s with relatively high selectivity for mono- and ylesters. In particular for the present invention, that uses mono- and diacetylesters in unsaturated polyester synthesis, this selectivity is highly valuable. This is an advantage because triacetylester acts as a plasticizer, and glycerol acts as a branching agent, both of which generally are only allowable in a relatively low amount.

In another embodiment of the invention, the invention s to a process for making glycerol, mono-, di- and triacetylglycerolester in which the amount of tri-ester produced relative to the ing glycerol, mono- and di-ester is less than 15 mol%, preferably less than 10 mol%.

In another embodiment of the ion, the invention relates to a process for making ol, mono-, di- and triacetylglycerolester in which the amount of glycerol produced relative to the resulting mono-, di- and tri-ester is less than 25 mol%, preferably less than 15 mol% and more preferably less than 10 mol%.

In a preferred embodiment, the invention relates to a process for making glycerol, mono-, di- and triacetylglycerolester in which the amount of monoester produced ve to the resulting glycerol, di- and tri-ester is about 20 mol% or more, preferably about 25 mol% 7264538_1 (GHMatters) P95050.NZ JENNYP or more, and even more preferred about 30 mol% or more. The amount of mono-ester will generally be about 50 wt% or less, and may be about 40 wt% or less.

In a further preferred embodiment, the ion relates to a process for making glycerol, mono-, di- and triacetylglycerolester in which the amount of diester produced relative to the resulting glycerol, mono- and tri-ester is about 20 mol% or more, preferably about 30 mol% or more, and even more preferred about 40 mol% or more. The amount of di- ester will generally be about 60 wt% or less, and may be about 50 wt% or less.

In a further embodiment, the invention relates to a process for making glycerol, monodi — and triacetylglycerolester wherein the amount of triester produced produced relative to the resulting glycerol, mono— and di-ester is between 1.0 mol% and about 15 mol%, and wherein the amount of glycerol produced produced ve to the resulting mono—, di— and tri- ester is between 5.0 mol% and about 25 mol%, The monoacetylester and diacetylester of glycerol can exist in two isomers (eg. 1- monoacetylester and 2—monoacetylester, and 1,2—diacetylester and acetylester). For the present invention, mono- and diacetylester will be used.

The acetylester mixture of glycerol, with a free glycerol content of less than 15 mol%, monoester in an amount n 25-50 mol%, diester between 30-50 mol% and trimester in an amount less than 15 mol% is very useful in the preparation of polyesters, and in particular of unsaturated polyesters that can be polymerized through radical polymerization to form articles. ol as such is used in the preparation of polyesters, like trimethylolpropane, as a branching agent. However, such branching agent generally is used in an amount of less than 3 wt% relative to the polyols. Higher amounts may lead to gelling of the polyesters during synthesis.

Higher amounts of trifunctional ls can be used, if combined with nctional acids or other chain rs. Well known monofunctional acids are fatty acids, used in the preparation of alkyd resins for coatings. In unsaturated polyesters, such fatty acids lead to lowering of the modulus, and to sed flexibility. Hence, the use of fatty acids (and with it, substantial amounts of ctional alcohols) is not preferred.

Generally — if used at all -, in unsaturated polyester synthesis, benzoic acid is used as monofunctional acid. Benzoic acid is made from e or toluene, being oil based raw materials.

The present invention allows substantial amounts of glycerol to be used in unsaturated polyesters, without one of the downsides of (i) much reduced tensile modulus, or (ii) the necessary use of synthetic raw materials. Thus, the present invention allows for an amount of 5 wt% or more of the alcohol component to be olacetylester, which is predominantly monoacetylester and diacetylester.

In a preferred rated polyester resin, the amount of glycerolacetylester is about 10 wt% or more, preferably about 20 wt% or more, and more preferably about 30 wt% or more of the alcohol component. It is possible to use the glycerol-acetylester mixture as (substantially) all of the alcohol component, although it may be preferred to use other tic or aromatic diols.

In order to lower the tendency of the unsaturated polyester to show yellowing, it is preferred to have a wholly tic unsaturated polyester. In contrast to the mono-acid c acid, the glycerol-acetylester allows for the ation of fully aliphatic unsaturated polyesters.

The glycerol and acetic acid mixture can be processed, for example with the organic tin based catalyst Fascat, at elevated temperature, like for example at 120 °C or higher, preferably 150 °C or higher, like for examp le 180 °C. Generally, the temperature will be about 260 °C or lower, preferably about 220 °C 0 r lower.

In a preferred embodiment, the invention relates to a s for making glycerol, mono-, di- and triacetylglycerolester in which the glycerol and acetic acid mixture is generally processed till an hydroxyl value of about 700 or lower is obtained, preferably about 600 or lower, and even more preferably about 550 or lower. Generally, the hydroxyl value will be about 300 or higher, preferably about 350 or higher, and most preferably about 400 or In a further preferred embodiment, the invention relates to a process for making glycerol, mono-, di- and triacetylglycerolester in which the glycerol and acetic acid mixture is lly processed till an acid value is obtained of about 60 or lower, ably about 50 or lower, and most preferably about 40 or lower. Generally, the acid value will be about 5 or higher, like about 10 or higher.

During processing, it may be useful to correct for acetic acid that may evaporate, depending on the vessel and processing conditions.

The glycerol and acetic acid preferably are from natural sources. Glycerol can be obtained as side t from bio-diesel production. Acetic acid can be produced from fermentation of natural alcohol. Preferably, at least the ol is from a natural source.

Unsaturated polyesters can be prepared by condensation polymerization reaction techniques as are known in the art. Representative sation polymerization reactions include polyesters prepared by the condensation of polyhydric alcohols and polycarboxylic acids or anhydrides. The polyalcohols part is also denoted as alcohol component; the polyacid part also as acid component. By ing the stoichiometry of the alcohols and the acids while maintaining an equivalent or excess of hydroxyl groups, hydroxy-functional polyesters can be readily produced to provide a wide range of desired molecular weights, unsaturation content and performance characteristics. In case the acid component is used in excess, an acid functional polyester is obtained.

The unsaturated polyester are derived from one or more aromatic and/or aliphatic rboxylic acids, the ides thereof, and one or more aliphatic and/or aromatic polyols. The carboxylic acids include the saturated and unsaturated polycarboxylic acids and the derivatives thereof, such as maleic acid, fumaric acid, succinic acid, adipic acid, c acid, dicyclopentadiene dicarboxylic acid, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, aromatic polycarboxylic acids, such as phthalic acid, isophthalic acid, terephthalic acid, etc. Anhydrides such as maleic anhydride, phthalic anhydride, trimellitic ide, or Nadic Methyl Anhydride (brand name for methylbicyclo[2.2.]heptene—2,3-dicarboxylic anhydride isomers) can also be used.

Representative saturated and unsaturated polyols which can be d with the carboxylic acids to produce hydroxy-functional polyesters include diols such as ethylene , dipropylene , trimethyl 1,3-pentanediol, neopentyl glycol, 1,2-propanediol, tanediol, 1,3-butanediol , 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,2- dimethyl-‘l,3-propanediol, clohexanedimethanol, 1,2-cyclohexanedimethanol, 1,3- cyclohexanedimethanol, ‘l,4-bis(2-hydroxyethoxy)cyclohexane, trimethylene glycol, tetramethylene , pentamethylene glycol, hexamethylene glycol, decamethylene glycol, diethylene glycol, ylene glycol, tetraethylene glycol, norbornylene glycol, 1,4- benzenedimethanol, 1,4-benzenediethanol, 2,4-dimethylethylenehexane-1,3-diol, 2- butene—1,4—diol, and polyols such as trimethylolethane, trimethylolpropane, hylolhexane, triethylolpropane, 1,2,4—butanetriol, glycerol, pentaerythritol, and dipentaerythritol.

At least part of the alcohol component is a acetylglycerolester mixture of the present invention.

Typically, the reaction between the polyols and the polycarboxylic acids is conducted at about 120° C to about 250° C in the presence or absence of an esterification catalyst such as dibutyl tin oxide.

Additionally, unsaturated polyesters can be prepared by tuting some or all of the s described above with epoxides and/or polyepoxides where acids and anhydride can open the oxirane ring to form the corresponding ester and hydroxy .

Representative polyepoxides include ethyleneoxide, propyleneoxide and those prepared by condensing a polyhydric alcohol or dric phenol with an epihalohydrin, such as epichlorohydrin, usually under alkaline conditions. Some of these condensation products are available commercially under the designations EPON or DER from Hexion Specialty Chemicals or Dow Chemical Company, respectively, and methods of preparation are representatively taught in US. Pat. Nos. 560; 2,582,985 and 694.

Another method to form unsaturated ters comprises chain extending the yl-functional polyesters by reacting the hydroxyl groups of a ndensed) polyester with chain extenders, preferably polyalkylene oxide or lactones such as polyethylene oxide, opylene oxide or caprolactone, valerolactone, and butyrolactone.

Monocarboxylic acids can be used for the preparation of the unsaturated polyesters to control molecular weight, functionality, and other teristic properties. The monocarboxylic acids can be aliphatic, cycloaliphatic, aromatic or mixtures thereof.

Preferably, the monocarboxylic acid contains 6 to 18 carbon atoms, such as benzoic acid, hexahydrobenzoic acid, and mixtures thereof. The use of (additional) monocarboxylic acid may be in particular advantageous if a glycerolacetylester is used with a relatively high hydroxyl functionality.

Monohydroxy compounds can be used in the practice of this invention to control molecular weight, functionality, and other characteristic properties. Examples of suitable monofunctional alcohols include ls with 4-18 carbon atoms such as 2-ethyl l, pentanol, hexanol, dodecanol, cyclohexanol and trimethyl cyclohexanol.

Hydroxy-functional acids can be used to replace some and/or all of the acids and polyols decribed above. Typical hydroxy acids that can be used include dimethylol propionic acid and hydroxypivalic acid.

The unsaturated polyesters generally have an acid number of about 60 or lower, preferably of about 30 or lower. The unsaturated polyesters generally will have a hydroxyl value of about 100 or lower, preferably about 50 or lower.

The unsaturated polyesters generally will have a molecular weight of about 600 or , ably about 1500 or higher. The molecular weight will be about 10000 or lower, preferably about 5000 or lower.

The unsaturated polyesters may be used in combination with vinylaromatic nds and/or acrylic compounds. Preferred compounds are styrene, divinylbenzene, alpha-methylstyrene and the like. Styrene is most common and is most preferred. Examples of alkenically unsaturated monomers are styrene, substituted styrenes such as vinyl-toluene or tert.butylstyrene, (C2-C6)-alkylesters of acrylic acid and methacrylic acid, d—methylstyrene, cyclic acrylates and methacrylates, halogenated styrenes, tanedioldimethacrylate and diallyl phthalate.

The unsaturation in the unsaturated ter is preferably the polymerized residue of c or maleic acid, and is a carbon-carbon double bond next to a carbonyl (C=O) group. Hence, ters that have only carbon-carbon unsaturations in fatty acids are not considered unsaturated polyesters in the present invention. In order to achieve sufficient unsaturation, it is red that about 10 mol% or more of the poly-acid component in the unsaturated polyester is a polymerized residue of fumaric or maleic acid, preferably about 40 mol% or more.

Substantial amount of the polyol component of the unsaturated polyester can be the glycerolacetate mixture of the present invention. It is preferred that at least 30 mol% of the polyolcomponent is the acetylglycerolester mixture obtainable per the present invention.

It has been ed that the minor amount of triacetylglycerolester in the acetylester mixture may have a plasticizing effect. In case that effect is not aimed at, it is preferred to use such an amount of acetylester mixture, that less than about 10 wt% of tylester is present in the unsaturated polyester with styrene, preferably less than about 6 wt%, and more preferably less than 4 wt%.

The polyester resin generally is used with ves to form a compound that can be applied in or to a mold, which can be cured to form an article.

To enhance the physical properties, commonly glass fibres are used with the unsaturated polyester resin in the compound. Part or all of the glass fibre can optionally be replaced by carbon fibre, sisal, jute, asbestos, cotton, flax, hemp, organic synthetic fibres, such as polyamide, ter, polypropylene or polyethylene, inorganic fibres such as quartz and beryllium and other metal fibres. The fibres may be present also in the form of continuous fibres or of a fibre mat, which is kept together by a suitable bonding agent, or in the form of. chopped filaments without binding agent. The length of the fibres used, particularly of the glass fibres, - if chopped fibres are used - may range from 0.5 mm to 50 mm. The fibre may be added in amounts of up to 80 % (wt) (calculated on the total compound).

The compound with the resin may further comprise fillers. The fillers that can be used may be, for instance, marl, antimony trioxide, silica flour, coconut shell flour, talcum, calcium carbonate, silicon oxide, clay, calcium silicate, wood flour, glass beads, titanium dioxide, aluminium silicate, aluminium hydrate, carbon black or gypsum anhydrite. The filler content incorporated may range from 5 up to 90 % by wt.

The resin can be used together with a catalyst for curing the resin to an article.

The catalyst applied may comprise, for instance, tert-butylperbenzoate, benzoyl peroxide, tert-butylperoxide, tert-butylperoctoate, di-tertbutylperoctoate, cyclohexanone peroxide, methylethylketone peroxide, acetylacetone peroxide or lperoxide, ations of these, optionally with hydrogen peroxide. Other suitable catalysts are UV sensitive initiators.

Further ves may comprise inhibitors, accelerators, e agents and low profile agents. Inhibitors are often used to provide sufficient ity of the moulding compound at ambient, temperature before the moulding process, the inhibitors also leave enough time for the flowing into the mould before the gelling commences. Examples of such inhibitors are hydroquinone and oquinone. Examples of accelerators are octoates, enates and amines, such as octoate, dimethylaniline, laniline and dimethyl para-toluidine. Suitable release agents are known, such as the stearates of zinc, m or aluminium, ates, silicons, polyvinylalcohol and waxes. Semi-permanent release agents can be used as well. Usual ofile additives are, for instance, thermoplastics. Examples of thermoplastics are homopolymers of methyl-methacrylate, ethylmethacrylate and butylmethacrylate, methylacrylate and ethylacrylate, styrene, copolymers of methylmethacrylate and other low-molecular weight alkylacrylates and alkyl20 methacrylates and copolymers of methylmethacrylate with small amounts of one or more of the following monomers: methacrylate, isobornylmethacrylate, acrylamide, hydroxyethyl-methacrylate, styrene, 2—ethylhexylacrylate, acrylonitrile, methacrylic acid, rylamide, olacrylamide and cetylstearylmethacrylate, or copolymers of styrene and acrylonitrile, copolymers of vinylchloride and vinylacetate, cellulose acetate te, cellulose acetate proprionate and styrene maleic anhydride copolymer.

Further, the usual ts or colourants can be added.

The invention is exemplified in the following examples, without being limited thereto.

EXAMPLES Examples 1-3 Acetic acid (HAc) and glycerol (Gly) are charged into a reaction flask, er with the catalyst, and are reacted at 0 °C for one hour, until distillate is no longer recovered. Thereafter, the temperature is increased stepwise up to 170-180 °C while keeping the still head temperature at 96-102 °C. The distillate is at intervals, titrated to determine the acid content, and lost acetic acid is charged to the on vessel in examples 1 and 2. ln example 3, no acetic acid is charged back. Processing is continued till the distillate reaches the theoretical value. The mole ratio of acid and glycerol charged, and the amounts of ol, mono-, di- and triacetylester are given in table 1, for three batches.

Table 1 Example Mole AV OH Gly Mono Di Tri ratio number HAc: Gly 1 1.75: 1 45 523 12.04 34.0 43.36 10.59 6.20 32.82 47.30 13.68 16.20 38.83 38.07 6.90 Example 4-10 and comparative example A With the glycerol-acetylester mixtures from es 1 and 2, unsaturated polyesters were prepared, while using the catalyst form the glycerolacetylester synthesis.

The components are as given in table 2.

Table 2 Reagent Example Glycerol- Glycol . 32.00 8.40 5.45 example Glycol Maleic . 50.00 2.72 anh dnde Fumaric 12.01 acid Propylene . . 34.6 7.84 ol col St rene 4.83 5.73 * glycerol BA is glycerol reacted with two moles of c acid (BA) ** s were charged on the basis of equivalent molecular weights (that is molecular weight per OH functionality, calculated from measured OH numbers).

*** Resins of examples 4 and 5 are the same formulation processed to different end points.

All the resin formulations contained the same levels of ves, namely: . st Fascat 4102 at a concentration of 0.13 wt% on BA and 0.3 wt% on HAc. o THQ 33% solution at 100 ppm on total weight . Triphenyl ate at 100 ppm on total weight . Copper naphthenate at 33 ppm on total weight . Sodium acetate (etherification inhibitor) at 50 ppm on base resin’s weight For resin A, the reaction vessel was heated till 160 °C and held at this temperature for 1 hour. Thereafter, the temperature was gradually increased to 220 °C.

After one hour, while distilling, xylene was added as azeotropic agent. Processing was continued until the amount of recovered water was about 80%. The reaction mixture is gradually cooled. The resins 4-10 were processed as described in Example 1. The final acid value was about 60 or less. The unsaturated polyester was blended with styrene at about 60 °C, further cooled, and stored in a steel container.

The resins have the properties, as shown in Table 3 Resin Non- styrenated resin Acid value (mg/g KOH) Viscosity at 75 °C (Poise) Styrenated resin Appearance of liquid Resin ICI viscosity Gel time at °C Exotherm time (min)* Exotherm temperature (OC)* Styrene content (wt (yo)** Liquid density, °C (g/ml) Solid density, °C (g/ml) tric shnnkage When cured, the unsaturated polyester had the following properties DMTA results are given in Table 4 chains/m3 ————— 150 693. 8 223.6 325.6 2558 1135.4 66. 7 __-_— 439 1 1722 “——403.3 186.7 361-6 2092 To = glass transition temperature E’r= the c storage modulus in the plateau region Mc= -average lar weight between cross-linked junctions Vc= cross-link density Heat deflection temoerature is oiven in table 5 ' HDT (°C) 56.5 73.5 88.5 87.0 37.5 54.0 62.0 Resin 7’s HDT was too low to be measured with available equipment, as the material already deflected under the load at room temperature (even at ~10°C).

Tensile properties are given in Table 6 Tensile strength Tensile modulus Strain at (MPa) (GPa) break (%) 42.0 i 3.4 2.9 i 0.2 2.2 i 0.4 1O 229:2.8 2.0i0.3 1.4i0.3 Examples 11-16 and comparative example B The resins were used to make glass fibre reinforced laminates. Laminates were ed from chopped strand mat glass fibre and resin catalysed with 0.15% cobalt octoate (6% solution) and 1% MEKP, using conventional hand lay-up technique. Laminates were cured at room temperature, followed by uring at 85°C for 2 hours. Properties are given in Table 7.

Tensile strength Tensile s Strain* (%) MPa GPa * The strain was measured at Max Tensile strength and not at complete severing of test specimens.

The above examples show that glycerolacetates (acetins) can be used as alcohol component in unsaturated polyester manufacture while keeping good properties.

Claims (26)

WHAT IS CLAIMED IS:

1. A process for the preparation of glycerolacetylesters, in which acetic acid and glycerol having the molar ratio of less than 2.5 are reacted in the presence of a stannous catalyst to produce a e of glycerol, mono-, di- and triacetylglycerolester.

2. The process according to claim 1, wherein the acetic acid and ol have a molar ratio of between about 1.5 and about 2.2.

3. The process according to any one of the preceding claims, wherein the resulting amount of triester relative to the resulting amounts of glycerol, monoester and diester is less than 15 mol%.

4. The s according to any one of the preceding claims, wherein the ing amount of triester relative to the resulting amounts of glycerol, monoester and diester is less than 10 mol%.

5. The process according to any one of the preceding claims, n the resulting amount of glycerol ve to the resulting amounts of monoester, diester and triester is less than 25 mol%.

6. The process according to any one of the preceding , wherein the resulting amount of glycerol ve to the resulting amounts of monoester, diester and triester is less than 15 mol%.

7. The s according to any one of the preceding claims, wherein the resulting amount of mono-ester relative to the resulting amounts of glycerol, diester and triester is about 20 mol% or more, and wherein the resulting amount of mono-ester relative to the resulting amounts of ol, diester and triester is about 50 wt% or less.

8. The process according to any one of the preceding claims, wherein the resulting amount of mono-ester relative to the resulting amounts of glycerol, diester and triester is 7264538_1 (GHMatters) P95050.NZ JENNYP about 30 mol% or more, and wherein the resulting amount of mono-ester ve to the ing amounts of glycerol, diester and triester is about 50 wt% or less.

9. The process according to any one of the preceding claims, wherein the resulting amount of di-ester relative to the resulting amounts of glycerol, monoester and triester is about 20 mol% or more, and wherein the resulting amount of di-ester relative to the resulting amounts of glycerol, ter and triester is about 60 wt% or less.

10. The s according to any one of the preceding claims, wherein the resulting amount of di-ester relative to the resulting amounts of glycerol, monoester and triester is about 40 mol% or more, and wherein the resulting amount of di-ester relative to the resulting amounts of glycerol, monoester and triester is about 60 wt% or less.

11. The process according to any one of the preceding claims, wherein the ing mixture has a hydroxyl value from about 300 to about 700.

12. The process according to any one of the preceding claims, wherein the resulting mixture has a hydroxyl value from about 300 to about 550.

13. The process ing to any one of the preceding claims, wherein the resulting mixture has an acid value of from about 5 to about 60.

14. The s according to any one of the ing claims, wherein the ing amount of triester relative to the resulting amounts of glycerol, monoester and diester is r than 1.0 mol%, and wherein the resulting amount of glycerol relative to the resulting amounts of monoester, diester and triester is about 5 mol% or more.

15. A mixture of glycerolacetylesters obtained by the process according to any one of the preceding claims. 7264538_1 (GHMatters) P95050.NZ JENNYP

16. The use of a mixture obtained by the process according to any one of claims 1-14, or the use of the mixture of claim 15, in the preparation of unsaturated polyesters that can be polymerized through radical polymerization to form articles.

17. An rated polyester comprising more than 5 wt% of the glycerolacetylesters ed by the process according to any one of claims 1-14, copolymerized in the polymer.

18. The unsaturated polyester according to claim 17, wherein the unsaturated polyester comprises more than 10 mol% of a poly-acid component in the unsaturated polyester, the poly-acid component being a rized residue of fumaric or maleic acid.

19. The unsaturated polyester according to any one of claims 17-18, wherein the unsaturated polyester comprises polystyrene.

20. An unsaturated polyester composition comprising: the unsaturated polyester according to any one of claims 17-19; and any one of fibres, fillers and/or catalysts.

21. A process of making an unsaturated polyester by reacting an α,ß-unsaturated carboxylic acid and at least a glycerolacetylester, n mono- and diacetylesters of glycerol are made from glycerol and acetic acid using an organotin catalyst, and wherein in making the unsaturated polyester the same organotin catalyst is used.

22. The process according to any one of claims 1-14 and 21 substantially as herein described with nce to any one of the Examples.

23. The e of olacetylesters according to claim 15 substantially as herein described with reference to any one of the Examples.

24. The use according to claim 16 substantially as herein described with nce to any one of the Examples.

25. The unsaturated ter according to any one of claims 17-19 substantially as herein described with reference to any one of the Examples.

26. The unsaturated polyester ition ing to claim 20 substantially as herein described with reference to any one of the Examples. 7410766_1 (GHMatters) P95050.NZ JENNYP