Thermosetting resin composition

Abstract

This invention relates to a radically curable resin composition comprising: a) An unsaturated polyester resin and/or a methacrylate functional resin, b) Reactive diluent, c) A copper salt, copper complex, iron salt and/or iron complex, and d) An enaminone.

Claims

1. A radically curable resin composition comprising: (a) an unsaturated polyester resin and/or a methacrylate functional resin, (b) a reactive diluent, (c) 0.001-10 mmol/kg (a)+(b) of a Fe.sup.2+, Fe.sup.3+, Cu.sup.+ or Cu.sup.2+ salt or complex; and (d) 0.5-150 mmol/kg (a)+(b) of an enaminone compound according to formula I: ##STR00005## wherein XC.sub.1-C.sub.20 alkyl, C.sub.6-C.sub.10 aryl, OR.sub.4 or NR.sub.5R.sub.6, R.sub.4, R.sub.5 and R.sub.6 are independently selected from C.sub.1-C.sub.20 alkyl; R.sub.1 is independently selected from H and optionally substituted C.sub.1-C.sub.18 alkyl, in which the optional substituents are hydroxyls; R.sub.2=hydroxyl substituted C1-C18 alkyl; R.sub.3C.sub.1-C.sub.20 alkyl or C.sub.6-C.sub.10 aryl; and optionally wherein R.sub.3 and X can form a (hetero)cycle.

2. The resin composition according to claim 1, wherein R.sub.1 is an optionally substituted C.sub.1-C.sub.12 alkyl.

3. The resin composition according to claim 1, wherein the compound (c) is present in the resin composition in such amount that the total amount of copper and iron in the resin composition is equal to or higher than 0.1 mmol/kg (a)+(b) and equal to or lower than 5 mmol/kg (a)+(b).

4. The resin composition according to claim 1, wherein the compound (c) is a Cu.sup.+ and/or Cu.sup.2+ carboxylate.

5. The resin composition according to claim 1, wherein the compound (c) is a Fe.sup.2+ and/or Fe.sup.3+ carboxylate.

6. The resin composition according to claim 1, wherein the ratio of molar amount of the enaminone compound and molar amount of copper and iron is from 2500:1 up to and including 1:2.

7. The resin composition according to claim 1, wherein the resin composition further comprises a base selected from the group consisting of alkaline bases, earth alkaline bases, amines and any mixture thereof.

8. The resin composition according to claim 1, wherein the reactive diluent is styrene.

9. The resin composition according to claim 1, wherein the reactive diluent is vinyl ester.

10. A multi-component system comprising at least two components, wherein one of the components is the resin composition according to claim 1 and at least one of the other components comprises a peroxide.

11. A multi-component system comprising at least three components, wherein a first one of the components is a resin composition comprising (a) an unsaturated polyester resin and/or a methacrylate functional resin and (b) a reactive diluent, a second one of the components is an accelerator solution comprising (1) an enaminone compound and (2) a Fe.sup.2+, Fe.sup.3+, Cu.sup.+ or Cu.sup.2+ salt or complex; wherein the ratio of molar amount of the enaminone compound to molar amount of copper and iron is from 15000:1 up to and including 1:2, and at least a third one of the components comprises a peroxide, wherein the enaminone compound is a compound of formula I: ##STR00006## wherein XC.sub.1-C.sub.20 alkyl, C.sub.6-C.sub.10 aryl, OR.sub.4 or NR.sub.5R.sub.6, R.sub.4, R.sub.5 and R.sub.6 are independently selected from C.sub.1-C.sub.20 alkyl; R.sub.1 is independently selected from H and optionally substituted C.sub.1-C.sub.18 alkyl, in which the optional substituents are hydroxyls; R.sub.2=hydroxyl substituted C1-C18 alkyl; R.sub.3C.sub.1-C.sub.20 alkyl or C.sub.6-C.sub.10 aryl; and optionally wherein R.sub.3 and X can form a (hetero)cycle.

12. The multi-component system according to claim 10, wherein the peroxide is a hydroperoxide or a mixture of hydroperoxides, whereby a perketal is considered a hydroperoxide.

13. The multi-component system according to claim 12, wherein the hydroperoxide is an organic hydroperoxide.

14. The multi-component system according to claim 10, wherein the peroxide is methyl ethyl ketone peroxide.

15. A method for radical curing of a resin composition, wherein the method comprises mixing the resin composition according to claim 1 with a peroxide and effecting curing of the resin composition at room temperature.

16. A method for radical curing of a resin composition comprising (a) an unsaturated polyester resin and/or a methacrylate functional resin and (b) a reactive diluent, wherein the method comprises: (i) mixing the resin composition with an accelerator solution comprising (1) an enaminone compound and (2) a Fe.sup.2+, Fe.sup.3+, Cu.sup.+ or Cu.sup.2+ salt or complex; wherein the ratio of molar amount of the enaminone compound to molar amount of copper and iron is from 15000:1 up to and including 1:2, and a peroxide, and (ii) effecting curing at room temperature, wherein the enaminone compound is a compound of formula I: ##STR00007## wherein XC.sub.1-C.sub.20 alkyl, C.sub.6-C.sub.10 aryl, OR.sub.4 or NR.sub.5R.sub.6, R.sub.4, R.sub.5 and R.sub.6 are independently selected from C.sub.1-C.sub.20 alkyl; R.sub.1 is independently selected from H and optionally substituted C.sub.1-C.sub.18 alkyl, in which the optional substituents are hydroxyls; R.sub.2=hydroxyl substituted C1-C18 alkyl; R.sub.3C.sub.1-C.sub.20 alkyl or C.sub.6-C.sub.10 aryl; and wherein R.sub.3 and X can form a (hetero)cycle.

17. The method according to claim 15, wherein the peroxide is a hydroperoxide or a mixture of hydroperoxides, whereby a perketal is considered a hydroperoxide.

18. The method according to claim 17, wherein the hydroperoxide is an organic hydroperoxide.

19. The method according to claim 15, wherein the peroxide is methyl ethyl ketone peroxide.

20. A structural part obtained by curing the resin composition according to claim 1 with a peroxide.

21. The structural part according to claim 20, wherein the structural part is selected from the group consisting of automotive parts, boat parts, chemical anchoring, roofing, construction parts, containers, relining, pipes, tanks, flooring and windmill blades.

22. A structural part obtained by curing the multi-component system according to claim 10.

Description

EXPERIMENTAL PART

(1) Unless otherwise indicated, the amounts given in the experimental part are weight amounts.

(2) Synthesis Resin A

(3) An unsaturated polyester was prepared by polycondensation of 105 parts of maleic anhydride, 314 parts of phthalic anhydride, 244 parts of 1,2-propylene glycol. The starting compounds were charged into a reactor equipped with condenser, stirrer, a temperature control system and an inlet for nitrogen. Under a gentle flow of nitrogen, the reaction mixture was heated up and maintained at a temperature of 210 C. The acid value dropped slowly and at the end of the process, vacuum was applied to help stripping the water from the reaction mixture to reach the targeted acid value and viscosity. An acid value of 52 mg KOH/g resin and a viscosity of 364 mPa.Math.s was reached. 600 g of this resin was diluted in a mixture of 340 g vinylbenzoate and 60 g divinyladipate resulting in resin A.

(4) Synthesis Resin B

(5) An epoxy vinylester resin (methacrylate functional resin) was prepared by charging into a reactor equipped with condenser, stirrer, a temperature control system and an inlet for nitrogen 67 g bisphenol A glycidylether, 13 g bisphenol A, 0.9 mg hydroquinone and 1.5 mg triphenylphosphine. Under a gentle flow of nitrogen, the reaction mixture was heated up to 135 C. Around 90 C., an exotherm starts which heats the reaction mixture up to 135 C. after which the reaction was maintained at this temperature for 30 min before cooling down to 110 C. Next 20 g methacrylic acid was added in 4 portions of 5 g with 15 minutes intervals followed by stirring the reaction mixture for an additional 2 hrs at this temperature. After cooling down to 90 C., 55 g hydroxyl ethyl methacrylate and 95 g dimethyl itaconate were added as reactive diluents and the reaction mixture was allowed to cool down to room temperature resulting in resin B.

(6) Monitoring of Curing

(7) In the Examples presented hereinafter it is mentioned, that curing was monitored by means of standard gel time equipment. This is intended to mean that both the gel time (T.sub.gel or T.sub.25.fwdarw.35 C.) and peak time (T.sub.peak or T.sub.25.fwdarw.peak) were determined by exotherm measurements according to the method of DIN 16945 when curing the resin with the peroxides as indicated in the Examples and Comparative Examples. The equipment used therefore was a Soform gel timer, with a Peakpro software package and National Instruments hardware; the waterbath and thermostat used were respectively Haake W26, and Haake DL30.

(8) Materials for Curing

(9) Cu=Rockwood Nuodex Cu 8 (copper naphthenate in mineral spirits, 8% Cu),

(10) Co=Akzo NL-49P (cobalt naphthenate in mineral spirits, 1% Co),

(11) Mn=Rockwood Nuodex Mn 10 (manganese ethylhexanoate, 10% Mn),

(12) Fe=Iron naphthenate in mineral spirits (12% Fe, Alfa Aesar),

(13) K=Caldic Liocat 110 (potassium octanoate, 10% K in ethanol),

(14) Al=Aluminium triacetate (Sigma Aldrich),

(15) Ca=Rockwood Nuodex 10 (Calcium ethylhexanoate, 10% Ca),

(16) V=Vanadium(V) oxytriisopropoxide (Aldrich),

(17) Ti=Titanium(IV) butoxide (Aldrich),

(18) Zr=Zirconium 2-ethylhexanoate in mineral spirits (10% Zr, abcr),

(19) Na=Sodium 2-ethylhexanoate (Alfa Aesar),

(20) Li=Lithium 2-ethylhexanoate (Alfa Aesar),

(21) Bi=bismuth 2-ethylhexanoate in mineral spirits (24.6% Bi, abcr).

(22) The peroxides used are commercially available from Akzo-Nobel except hydrogen peroxide which was obtained from Aldrich.

(23) Synthesis of Enaminones Typical Procedure:

(24) In a round bottom flask charged with 13 g of ethylacetocetate (100 mmol) and 100 ml toluene, was added 6.1 g ethanol amine (100 mmol). After fitting a Dean-Stark set up, water was azeotropically removed. Heating was continued until no water was any longer formed. After evaporation of the solvent, the enaminone was obtained quantitatively.

(25) Following a similar procedure, the following enaminones were prepared based on: ethylacetoacetate, acetyl acetone, benzoylacetone, 1,3-cyclohexanedione and N,N-diethylacetoacetamide as ketones and ethanol amine, diethanolamine, N-methylethanolamine, piperidine, p-toluidine and Jeffamine D230 (polyether diamine) as amines.

(26) Depending on the starting materials and the enaminone formed, other solvents like for example ethanol can also be used for the azeotropic water removal.

(27) Enaminones A-K according to the following formula are obtained. X, R1, R2 and R3 are specified in Table 1.

(28) ##STR00003##

(29) TABLE-US-00001 TABLE 1 Enaminone R.sub.1 R.sub.2 R.sub.3 X A H CH.sub.2CH.sub.2OH CH.sub.3 OCH.sub.2CH.sub.3 B H CH.sub.2CH.sub.2OH CH.sub.3 CH.sub.3 C CH.sub.2CH.sub.2OH CH.sub.2CH.sub.2OH CH.sub.3 CH.sub.3 D CH.sub.3 CH.sub.2CH.sub.2OH CH.sub.3 CH.sub.3 E CH.sub.2CH.sub.2CH.sub.2CH.sub.2CH.sub.2 (R1 and CH.sub.3 CH.sub.3 R2 form a cycle) F H C.sub.6H.sub.4CH.sub.3 CH.sub.3 CH.sub.3 G H CH.sub.2CH.sub.2OH CH.sub.3 C.sub.6H.sub.5 H H C.sub.6H.sub.4CH.sub.3 CH.sub.3 C.sub.6H.sub.5 I H CH.sub.2CH.sub.2OH CH.sub.3 N(CH.sub.2CH.sub.3).sub.2 J H Polymeric with CH.sub.3 CH.sub.3 enaminone substituent K H CH.sub.2CH.sub.2OH CH.sub.2CH.sub.2CH.sub.2 (R.sub.3 and X forms cycle) L H CH.sub.2CH.sub.2OH C.sub.6H.sub.5 C.sub.6H.sub.5

(30) An enaminone according to the following formula has also been prepared (enaminone J) (Jeffamine D230 was used as amine):

(31) ##STR00004##
with X.sub.1X.sub.2CH.sub.3, R.sub.1R.sub.7H, R.sub.3R.sub.8CH.sub.3 and R.sub.9=polyether.

Example 1 and Comparative Experiments A

(32) To 100 g of resin A was added 1 g enaminone A, and 3 mmol of various metal compounds per kg of resin A. After stirring for 3 min, 3% Butanox M50 (peroxide) was added and the cure was monitored with the gel time equipment. The results are shown in table 2.

(33) TABLE-US-00002 TABLE 2 Peak Gel time Peak time temperature Ex Metal Enaminone (min) (min) ( C.) 1.1 Cu A 0.9 2.1 156 1.2 Fe A 1.2 3.1 152 A1 A >1200 A2 Cu >1200 A3 Fe >1200 A4 Co >1200 A5 Co A >1200 A6 V >1200 A7 V A >1200 A8 Mn >1200 A9 Mn A >1200 A10 K A >1200 A11 Al A >1200 A12 Ca A >1200 A13 Ti A >1200 A14 Zr A >1200 A15 Bi A >1200 A16 Cu A >1200 wire A17 Fe A >1200 wire

(34) This table demonstrates that for an efficient curing of an unsaturated polyester (UP) diluted in a vinyl ester reactive diluent both an enaminone and copper or iron salt/complex are needed. Employing only enaminone (A1) resulted in no curing, similar to employing only copper salt/complex (A2) or iron salt/complex (A3).

(35) When employing Co, V or Mn salt/complex with or without enaminone (A4-A9), i.e. transition metals which are frequently used in curing UP resins, also no cure was observed. This illustrates the fact that not all transition metal salts/complexes in combination with enaminones can result in an efficient curing but only iron salt/complex and copper salt/complex in combination with enaminones are able to result in efficient curing.

(36) Further, from A16 and A17, in which Cu wire respectively Fe wire has been added to the reaction tube, it is clear that using pure Cu compound or pure Fe compound does not give acceleration. Only when using a Cu or Fe salt/complex (examples 1.1 & 1.2), efficient acceleration is obtained.

Example 2 and Comparative Experiments B

(37) To 100 g of Palatal P4-01 (unsaturated polyester diluted in styrene, commercially available from DSM Composites Resins, Schaffhausen, C H) was added enaminone B and various metal salts, such that the amounts of metal were as stated in table 3. After stirring for 3 min, 2% Butanox M50 was added and the cure was monitored with the gel time equipment. The results are shown in table 3.

(38) TABLE-US-00003 TABLE 3 Amount amount (mmol/ mmol/ kg kg Gel Peak Peak Palatal Palatal time time temperature metal P4-0) enaminone P4-01 (min) (min) ( C.) 2.1 Cu 0.126 B 6.2 9.6 15.9 146 B1 Cu 0.126 >1200 B2 Co 0.16 B 6.2 34.2 68.7 88 B2 Co 0.16 52.3 89.1 81

(39) This table illustrates that the combination of enaminone and copper salt is a very efficient combination also for curing unsaturated polyester resins in styrene as reactive diluent.

(40) In case Co salt is used in an unsaturated polyester in styrene (B3), the addition of enaminone (B2) results in a small rate enhancement. Employing however Cu salt instead of Co salt (2.1 vs B2) a significantly more efficient curing is observed even when a lower amount of Cu is used.

Examples 3 and Comparative Experiments C

(41) To 100 g of Palatal P4-01 was added 1.5 mmol enaminone B and Cu, Fe, Mn, or Co salts/complexes in various amounts, such that the amounts of metal were as stated in table 4 below. After stirring for 3 min, 2% Butanox M50 was added and 25 g of the formulations were poured in plastic beakers resulting in castings with a thickness of approximately 1 cm. After 24 h, the Barcol hardness of the bottom of the casting was determined with a Barcol 934-1 hardness tester according to ASTM D2583. The results are given in Table 4.

(42) TABLE-US-00004 TABLE 4 Amount metal Metal (mmol/kg Palatal P4-01) Barcol 934-1 3.1 Cu 0.013 45-50 3.2 Cu 0.13 40-45 3.3 Fe 0.13 10-15 3.4 Fe 1.29 40-45 C1 none 0 0 C2 Co 0.17 0-5 C3 Mn 0.18 0
These examples clearly demonstrate that the combination of enaminone with Cu or Fe salt gives cured castings with increased Barcol hardness (examples 3.1-3.4) compared to when using enaminone alone (comp ex C1). The Barcol hardness is a measure for the stiffness of the cured material and as such an indication for the degree of cure. The combinations of enaminone with other transition metal salts/complexes like Mn or Co give no or only a minor improvement of the hardness (comp ex C2&C3).

Example 4

(43) To 100 g of Palatal P4-01 was added various enaminones and various metal salts, such that the amounts of metal were as stated in table 5. After stirring for 3 min, 2% Butanox M50 was added and the cure was monitored with the gel time equipment. The results are shown in table 5.

(44) TABLE-US-00005 TABLE 5 mmol/ mmol/ kg kg Gel Peak Peak Palatal Palatal time time temperature Metal P4-01 Enaminone P4-01 (min) (min) ( C.) 4.1 Cu 1.26 B 6.2 6.4 10.8 128 4.2 Cu 1.26 C 9.7 19.8 35.8 112 4.3 Cu 1.26 E 6 34.3 55.1 116 4.4 Cu 1.26 F 5.2 29.8 44.3 115 4.5 Cu 1.26 G 5.8 8.8 15.8 117 4.6 Cu 1.26 H 4 122 169 41 4.7 Cu 1.26 J 5 6.4 10 130 4.8 Fe 1.9 B 6.2 7.4 17.6 116 4.9 Fe 1.1 J 5 11.9 24.5 87

Example 5

(45) To 100 g of resin A was added various enaminones and various metal salts, such that the amounts of metal were as stated in table 6. After stirring for 3 min, 3% Butanox M50 was added and the cure was monitored with the gel time equipment. The results are shown in table 6.

(46) TABLE-US-00006 TABLE 6 Peak tem- mmol/ Gel Peak pera- mmol/kg kg time time ture metal resin A Enaminone resin A (min) (min) ( C.) 5.1 Cu 3 B 20 1.8 3.3 185 5.2 Cu 0.5 D 10 8.3 11.6 192 5.3 Cu 3 I 20 2.9 6.7 178 5.4 Cu 0.55 K 6.9 27.2 36.8 177 5.5 Cu 0.5 G 10 10.3 13.8 195 5.6 Fe 5 D 10 1.8 5.5 185 5.7 Fe 0.5 D 10 9.8 16.1 93 5.8 Cu 3 L 10 23.8 44.5 146 5.9 Fe 3 L 30 8.5 27.1 59 5.10 Cu + 0.25 + 0.25 D 10 7.8 11 193 Fe

(47) Examples 4 and examples 5 demonstrate that various enaminones can be used in combination with copper and/or iron salt in order to obtain an efficient curing. Examples 4.7 and 4.9 demonstrate that a polymeric bis-enaminone can be used.

(48) Example 5.4, in which a trans-enaminone is used, demonstrates that besides cis-enaminones, also trans-enaminones can be used according to the invention. Example 5.10 demonstrates that besides Cu salt or Fe salt alone also mixtures of Cu and Fe salts can be used which, when comparing to examples 5.7 and 5.2, appears to be even a bit more active.

Example 6

(49) To 100 g of Palatal P4-01 was added 1.5 mmol enaminone B and copper naphthenate in various amounts as stated in table 7. After stirring for 3 min, 2% Butanox M50 was added and the cure was monitored with the gel time equipment. The results are shown in table 7.

(50) TABLE-US-00007 TABLE 7 amount amount mmol/ mmol/kg kg Gel Peak Peak Palatal Palatal time time temperature metal P4-01 enaminone P4-01 (min) (min) ( C.) 6.1 Cu 0.126 B 15 4.6 8.6 151 6.2 Cu 0.063 B 15 5.3 9.8 155 6.3 Cu 0.031 B 15 5.7 11.2 155 6.4 Cu 0.0068 B 15 7.3 14.8 147 6.5 Cu 0.0025 B 15 8.5 17.8 138 6.6 Cu 0.0013 B 15 9.4 19.3 131

(51) These examples demonstrate that even with copper amounts as low as 1.3 micromol/kg still an efficient curing can be obtained, being indicative of the fact that this is a very efficient cure system.

(52) It should be noted as further comparison that when employing Cobalt salt in an amount as low as 0.0013 mmol/kg. no cure could be detected with the gel time equipment and this finding further illustrates the efficiency of this cure system.

Example 7

(53) To 100 g of Palatal P4-01 was added various amounts of enaminone B and 0.126 mmol copper naphthenate as stated in table 8. After stirring for 3 min, 2% Butanox M50 was added and the cure was monitored with the gel time equipment. The results are shown in table 8.

(54) TABLE-US-00008 TABLE 8 amount amount mmol/ mmol/kg kg Gel Peak Peak Palatal Palatal time time temperature metal P4-01 enaminone P4-01 (min) (min) ( C.) 7.1 Cu 1.26 B 123 1.2 3.3 140 7.2 Cu 1.26 B 62 1.4 3.6 138 7.3 Cu 1.26 B 31 2.2 4.4 134 7.4 Cu 1.26 B 15 3 5.6 131 7.5 Cu 1.26 B 3.1 13.1 24.1 116 7.6 Cu 1.26 B 1.5 27.5 43.8 50

(55) These examples illustrates that various amounts of enaminone can be used.

Example 8

(56) To 100 g of various resins (see Table 9), 0.62 mmol enaminone B and 0.127 mmol copper naphthenate were added. After stirring for 3 min, 2% Butanox M50 was added and the cure was monitored with the gel time equipment. The results are shown in table 9.

(57) TABLE-US-00009 TABLE 9 Gel Peak Peak time time temperature Resin type Diluent (min) (min) ( C.) 8.1 Synolite- DCPD Styrene 14.6 21.5 138 8388-N- (40) 1 8.2 Atlac- Bisphenol Styrene 18.8 29.1 135 580 A (47) vinylester urethane 8.3 Palatal Ortho Styrene 6.3 8.8 178 P6-01 resin (35) 8.4 resin B Epoxy HEMA DMI 31.7 44.9 53 vinyl (22) (38) ester

(58) These examples in combination with example 1 demonstrate that various resins i.e. ortho resins, DCPD resins, epoxy vinylester resins, and urethane vinylester resins diluted in various reactive diluents like styrene, vinyl benzoate, hydroxyl ethyl methacrylate and dimethyl itaconate can be employed in the present invention.

Example 9

(59) To 100 g of various resins was added various amounts of various enaminones and various amounts of copper naphthenate and optionally various amounts of base e.g. potassium octanoate (see table 10). After stirring for 3 min, 2% Butanox M50 was added and the cure was monitored with the gel time equipment. The results are shown in table 10.

(60) TABLE-US-00010 TABLE 10 Cu Amount K Peak Peak (mmol/kg (mmol/kg (mmol/kg Gel time time temp Resin resin) enaminone resin) resin) (min) (min) ( C.) 9.1 Palatal 0.0068 B 15 7.3 14.8 147 P4-01 9.2 Palatal 0.0068 B 15 12.8 4.4 10.9 144 P4-01 9.3 Palatal 0.0025 B 15 8.5 17.8 138 P4-01 9.4 Palatal 0.0025 B 15 14.4 5 12.9 138 P4-01 9.5 Palatal 0.0013 B 15 9 19.3 131 P4-01 9.6 Palatal 0.0013 B 15 12.8 4.9 14.6 122 P4-01 9.7 Palatal 1.26 F 11 25 37 120 P4-01 9.8 Palatal 1.26 F 11 12.8 3.9 7.4 128 P4-01 9.9 Palatal 1.26 F 5 29.8 44.3 115 P4-01 9.10 Palatal 1.26 F 5 12.8 4.3 8 125 P4-01 9.11 Synolite 1.26 B 6.2 14.6 21.5 138 8388 9.12 Synolite 1.26 B 6.2 12.8 6.6 11.1 145 8388

(61) These examples demonstrate that the cure of a resin composition according to the invention can even be further enhanced by the addition of a base.

Example 10 and Comparative Experiment C

(62) To 100 g of Palatal P4-01 was added 0.6 mmol enaminone B and 0.126 mmol copper naphthenate. After stirring for 3 min, various amounts of various peroxides were added and the cure was monitored with the gel time equipment. The results are shown in table 11.

(63) TABLE-US-00011 TABLE 11 Gel Peak Peak Amount time time temperature peroxide type (%) (min) (min) ( C.) 10.1 Butanox Methyl ethyl 1 11.2 16.7 113 M50 ketone peroxide 10.2 Butanox 2 6.4 10.8 128 M50 10.3 Butanox 3 4.7 9.6 137 M50 10.4 Trigonox Acetylacetone 2 28.5 37.7 130 44B peroxide 10.5 Butanox Methyl ethyl 2 6.3 10.7 137 LPT-IN ketone peroxide 10.6 Hydrogen peroxide (30% in 2 5.3 13.3 113 water) 10.7 Trigonox Cumyl 2 88.6 123.2 43 239 hydroperoxide 10.8 Cyclonox Cyclohexanone 2 6.7 10.4 109 LE-50 peroxide

(64) These examples demonstrate that various peroxides in various amounts can be applied in the present invention.

Example 12

(65) To 100 g of resin A was added 1 g enaminone A and 3 mmol copper salt per kg of resin A. After stirring for 3 min, 3% of various peroxides were added and the cure was monitored with the gel time equipment. The results are shown in below table.

(66) TABLE-US-00012 TABLE 12 Peak Peak Gel time time temperature Peroxide (min) (min) ( C.) 12.1 Butanox M50 1.2 2.7 154 (methylethylketone peroxide) 12.2 Perkadox CH50L (dibenzoyl 44.5 63.4 115.5 peroxide)

(67) The examples 12.1 and 12.2 show that different peroxides can be used.

Example 13

Preparation of Accelerator Solution

(68) 1.49 g Nuodex Cub was diluted with 5.97 g vinyl benzoate, resulting in a 1.6% Cu solution. 14.9 g enaminone D was dissolved in 9.4 g ethanol resulting in an enaminone solution.

(69) An accelerator solution was prepared by mixing 2 g of the 1.6% Cu solution with 2.56 g of the enaminone solution. After stirring for 5 min, the accelerator solution was left to stand overnight.

(70) Use of the Accelerator Solution

(71) 0.456 g of the accelerator solution was added to 100 g of resin A (resulting in 10 mmol enaminone D/kg resin A and 0.5 mmol Cu/kg resin A analogues to example 4.2) and cured using 3% Butanox M50 resulting in a gel time of 7.9 min, a peak time of 11.6 min and a peak temperature of 193 C.

Example 14

(72) Preparation of Accelerator Solution

(73) An accelerator solution was prepared by mixing and dissolving 4 g butoxy ethanol, 2 g propylene glycol, 1.8 g enaminone B and 2 g copper naphthenate (8% Cu). After gentle heating and cooling down overnight, a clear accelerator solution was obtained.

(74) Use of the Accelerator Solution

(75) 0.5 g of the accelerator solution was added to 100 g Palatal P4-01 (resulting in 6.2 mmol enaminone B/kg Palatal P4-01 and 1.26 mmol Cu/kg Palatal P4-01 analogues to example 2.1). After stirring for 5 min, 2% Butanox M50 was added and the cure was monitored with the gel time equipment resulting in a gel time of 6.2 min, a peak time of 10.4 min and a peak exotherm of 126 C.

(76) Examples 13 and 14 illustrate that a mixture of enaminone and copper salt or iron salt can be used for accelerating the peroxide curing of unsaturated polyester resins. Comparing example 5.2 (gel time 8.3) with example 13 (gel time 7.9) and example 2.1 (gel time 9.6 min) with example 14 (gel time 6.2 min) demonstrate that using a premixed solution of the enaminone and the copper/iron, the cure can be further accelerated compared to adding the individual accelerator ingredients to the resin just before the peroxide is added, although sometimes the effect is minimal.