Abstract:
A low organic emission composition comprising a di-alkoxylated bisphenol-A dimaleate urethane dimethacrylate hybrid resin, an alkoxylated bisphenol-A diacrylate or dimethacrylate, ethylene glycol dimethacrylate and other vinyl monomers. The composition is useful in such applications as a substitute for prior art resins, such as polyester/vinyl ester based resins, typically used in fiberglass reinforced plastic applications.

Description:
TECHNICAL FIELD 
     This invention relates to low organic emission compositions comprising an alkoxylated bisphenol-A based dimethacrylate urethane hybrid polymer in combination with one or more alkoxylated bisphenol-A dimethacrylate monomers. These compositions find use in applications such as fiberglass reinforced plastic applications. The polymers made from the compositions of the present invention may substitute for polyester/vinyl ester based polymers used in the art. 
     BACKGROUND OF THE INVENTION 
     U.K. Patent Nos. 1,352,063; 1,465,359; and U.S. Pat. No. 4,457,818 disclose vinyl urethane resins. The resins are prepared from a diisocyanate, a hydroxyl-terminated ester of acrylic or methacrylic acid, and a bisphenol-A based ester of maleic or fumaric acid. The resins are polymerized with styrene to give a thermoset polymer. These polymers are said to have improved properties over prior art vinyl urethane resins. 
     Smeal et al., in U.S. Pat. Nos. 5,292,841; 5,393,830; 5,492,668; 5,501,830; 5,500,171; and 5,534,211 disclose formations of low organic emission polyester based polymers with alkoxylated bisphenol-A dimethacrylate esters, ethylene glycol dimethacrylate and other vinyl monomers. In these polymers, the use of styrene is either eliminated, or significantly minimized. The results are polymers with typical physical properties that give off lower levels of organic emissions during the polymerization process. 
     SUMMARY OF THE INVENTION 
     Alkoxylated bisphenol-A dicarboxylic acid based dimethacrylate urethane hybrid resins (referred to herein as &#34;hybrid resins&#34;) are typically prepared, as is known in the art, by reacting a polyol, an unsaturated dicarboxylic acid (herein interchangeable with anhydride), a hydroxyl terminated methacrylate ester and a diisocyanate. One typical synthesis of a hybrid resin includes reacting two moles of alkoxylated Bisphenol-A with one mole of an unsaturated dicarboxylic acid. The resulting diester is reacted with two moles of diisocyanate, and two moles of the hydroxyl terminated methacrylate ester. The hybrid resin has vinyl terminated end groups and a diacid double bond that act as cross-linking sites with other methacrylates such as alkoxylated bisphenol-A diacrylates or dimethacrylates (ABAD), ethylene glycol dimethacrylates (EGDM), and vinyl monomers. The hybrid resin is then blended, as is known in the art, with the alkoxylated bisphenol-A dimethacrylate, styrene and or vinyl toluene monomers and the remaining constituents. The resulting mixture is then polymerized. 
     As with the polymers disclosed in the Smeal et al references, the polymers of the present invention give off lower levels of volatile emissions during polymerization than similar polymers in the art. The polymers of the present invention will emit no more than about 20 g/m 2  as measured by Rule 1162 Standard Method for Static Volatile Emissions of the South Coast Air Quality Management District (California), as set forth in the Smeal et al patents. The benefits associated with polymers, useful in laminating operations, emitting low levels of organic emissions is well known in the art. The present invention is the first known application to the art of these hybrid polymers in this type of application. Additionally, these polymers are useful in molding applications. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The resins of the present invention include compositions comprising about 20-50 wt % (based on the weight of the final product) of at least one hybrid resin. Preferably, 30-40 wt % is added. The preferred hydroxyl terminated methacrylate ester is hydroxy ethyl methacrylate (&#34;HEMA&#34;). The preferred diacid is maleic acid or anhydride. Preferred diisocyanates include toluene, methylene, isophorone and 4,4-dicyclohexylmethane diisocyanates. Preferred hybrid resins are di-6-ethoxylated bisphenol-A maleate urethane dimethacrylate, di-3-ethoxylated bisphenol-A maleate urethane dimethacrylate, and di-4-propoxylated bisphenol-A maleate urethane dimethacrylate. 
     The ABAD comprises about 25-45 wt % of the product. Preferably 30-40 wt % is used. The preferred ABADs include 3-, 6-, and 10-ethoxylated bisphenol-A dimethacrylate, and mixtures thereof. 
     Ethylene glycol dirnethacrylate comprises about 10-20 wt % of the final product, preferably 15-20 wt % is used. Vinyl monomers comprise about 5-20 wt % of the final product. Preferably 10-15 wt % is used. Preferred vinyl monomers include styrene and vinyl toluene. 
     Tables I through V summarize experimental work performed by applicants in comparing various formulations to styrene control polymers. Typical wet polymer and mechanical properties were measured; viscosity, gel time, Rule 1162 volatile emissions, and barcol hardness cure development. These tests are well known in the art, and are set forth in detail e.g. in the Smeal et al patents listed above, and incorporated herein by reference. Polymer clear castings were prepared for tensile, flexural, heat distortion temperature (HDT), and water absorption properties. A standard room temperature cure initiator, and promoter were used. The castings were cured at room temperature for two hours and post-cured for two hours at 100° C. 
     Table I includes polymers utilizing 3- or 6-ethoxylated BPA based maleate/diester monomers. Toluene diisocyanate (TDI) and hydroxy methyl methacrylate (HEMA) were reacted with the maleate/diester to make the polyurethane hybrid resin. Polymers K-11, and N-11 contained the 6-EBPA based urethane resin with selected combinations of ABAD monomers. Polymers R-11, F-12 and R-12 contain the 3-EBPA urethane based resin with the ABAD monomers. Polymer G-12 is also a styrene control, and contains the 3-EBPA resin. Good compatibility was observed with these systems. Polymers containing both the 3- and 6-EBPA based vinyl urethane resins had much lower emissions than the styrene control. 
     Table II shows results of polymers containing di-4-propoxylated BPA (UPBPA) maleate urethane diester resin. Again, TDI was used as the monomeric base material for the urethane reaction. Three individual batches (307-07, 307-33, and 307-44) of the 4-PBPA vinyl urethane resin were evaluated with the ABAD monomers and with a styrene control. Polymer M-12 which was repeated twice had 25% resin while polymer 1-12 contained 30%. These formulations had typical viscosities that were comparable to the styrene control J-12. 
     Mechanical properties of the polymers containing the 4-PBPA vinyl urethane based resin/ABAD monomer blend combinations were comparable to the styrene controls. The barcol hardness development was better than the styrene control. Overall, better physicals were seen with polymers Y-12 and Z-12 containing approximately 43% of the urethane resin. 
     Table III lists polymers containing a 4-PBPA vinyl urethane resin using MDI as the monomeric base material for the urethane reaction instead of TDI. Two polymers were prepared and compared to a styrene control. The 4-PBPA MDI urethane resin had a higher viscosity than those using TDI. This is reflected in the much higher polymer viscosities with the MDI based resins compared to previous TDI formulations. 
     Table IV lists polymers containing the 4-PBPA vinyl urethane resin using isophorone diisocyanate as the monomeric base isocyanate for the urethane reaction. Polymer A-14 was the styrene control, while polymers B-14 through D-14 contained various combinations of resin with ABADs, EGDM and vinyl toluene. Formulation B-14 overall showed the best properties compared to the control. Polymer B-14 had lower volatile emissions and similar mechanical properties compared to A-14. The barcol hardness cure developments of these polymers are also better than the control. The styrene control had a sluggish and long interval cure time compared to the polymers containing the dimethacrylate monomers. 
     Table V lists formulations containing a vinyl terminated urethane polymer using a hydrogenated form of MDI as the pre-polymer in the diisocyanate reaction. Control formulation N-14 contains 59% of the resin and 41% styrene, while the remaining polymers (O-14, P-14, Q-14, and R-14) all contain different combinations of dimethacrylate esters and vinyl toluene. Mechanical properties of the polymers were comparable to the styrene control and overall had lower emissions. Viscosities of these materials are in acceptable ranges for both laminating and molding applications. 
     
                                           TABLE I__________________________________________________________________________LOE POLYMERS CONTAINING 3&amp;6EBPA URETHANE DIMETHACRYLATERESINS WITH SELECTIVE COMBINATIONS OF 6EBPA DIMETHACRYLATE,ETHYLENE GLYCOL DIMETHACRYLATE &amp; VINYLTOLUENE MONOMERS(TDI USED AS MONOMERIC BASE MATERIAL FOR URETHANE REACTION)RESIN #        K-11    N-11    R-11    F-12    G-12    R-12__________________________________________________________________________COMPOSITION ,%146-178 6EBPa Vinyl Urethane          30      25      --      --      --      --Resin146-187 3EBPa Vinyl Urethane          --      --      30      25      50      40Resin6-EBPA DIMETHACRYLATE          40      40      40      40      --      30ETH. GYLCOL    20      20      20      25      --      20DIMETHACRYLATEVINYL TOLUENE (MONOMER)          10      15      10      10      --      10STYRENE (MONOMER)          --      --      --      --      50      --MOD L, 25% HQ (INHIBITOR)          0.12    0.10    0.10    0.07    0.20    0.05COBALT 12%, (PROMOTER)          0.30    0.30    0.35    0.30    0.30    0.30POTASSIUM 15%, 0.20    0.20    0.233   0.20    0.20    0.20(COPROMOTER)DMAA, (COPROMOTER)          0.30    0.30    0.35    0.30    0.30    0.30RESIN PROPERTIES (1)BRKFLD VISCOSITY @ 77 F.,          472     192     806     461     891     1525(CPS)RM. TEMP. (77 F.) GEL TIME:          22.0    21.0    30.0    24.5    --      22.0(MIN.)INTERVAL, (MINUTES)          6.0     6.0     6.4     6.9     --      4.6PEAK EXOTHERM, (F.)          282     307     288     302     --      282BARCOL HARDNESS-45 MINUTES     39      39      42      41      --      391 HOUR         41      41      43      43      --      402 HOUR         40      41      43      44      --      433 HOUR         40      40      43      43      --      434 HOUR         40      40      43      44      --      4424 HOURS       40      44      43      45      --      441162 VOLATILE EMISSIONS,          17.0    28.5    18.2    20      40.6    23.6(G/M2)EMISSION TIME, (MINUTES)          7.0     9.5     13.5    11.5    22.5    8PHYSICAL PROPERTIES OFRESIN CLEARCASTINGS: (1), (2)TENSILE STRENGTH, (PSI)          7,980 +/- 1,470                  7,350 +/- 1,040                          8,700 +/- 900                                  7,010 +/- 1,880                                          10,110 +/- 2,550                                                  7,510 +/- 700TENSILE MODULUS, (MPSI)          0.344 +/- 0.021                  0.371 +/- 0.008                          0.506 +/- 0.019                                  0.521 +/- 0.028                                          0.541 +/- 0.012                                                  0.564 +/- 0.014TENSILE ELONGATION, (%)          3.5 +/- 0.9                  2.6 +/- 0.5                          2.1 +/- 0.3                                  1.5 +/- 0.5                                          2.5 +/- 1.3                                                  1.5 +/- 0.1FLEXURAL STRENGTH, (PSI)          16,550 +/- 670                  13,690 +/- 930                          14,730 +/- 1,290                                  15,410 +/- 380                                          20,780 +/- 300                                                  15,660 +/- 3,130FLEXURAL MODULUS, (MPSI)          0.437 +/- 0.007                  0.419 +/- 0.025                          0.460 +/- 0.005                                  0.467 +/- 0.003                                          0.509 +/- 0.010                                                  0.529 +/- 0.038HEAT DISTORTION TEMP:          155     164     170     167     170     169DTUL, F.WATER ABSORPTION @ 150 F.24 HOURS:      1.00    0.96    0.83    0.85    0.44    0.757 DAYS:        1.64    1.40    1.29    1.31    0.67    1.36__________________________________________________________________________ (1)-1.5% HIPOINT 90 MEKP ROOM TEMPERATURE INITIATOR (2) 2 HOUR ROOM TEMPERATURE (77 F.) CURE, 2 HOUR POSTCURE @ 100 C. TOLUENE DIISOCYANATE WAS USED AS THE PREPOLYMER AND REACTED WITH THE MALEIC/DIESTER TO MAKE THE VINYL URETHANE RESIN 
    
     
                                           TABLE II__________________________________________________________________________LOE POLYMERS CONTAINING 4PBPA URETHANE DIMETHACRYLATERESINS WITH SELECTIVE COMBINATIONS OF 6EBPA DIMETHACRYLATE,ETHYLENE GLYCOL DIMETHACRYLATE &amp; VINYLTOLUENE MONOMERS(TDI USED AS MONOMERIC BASE MATERIAL FOR URETHANE REACTION)__________________________________________________________________________RESIN #           J-12    J-12    M-12    M-12__________________________________________________________________________COMPOSITION, %            (REPEAT)        (REPEAT)307-07 4PBPA Vinyl Urethane Resin             56.1    --      25      --307-33 4PBPA Vinyl Urethane Resin             --      --      --      --307-44 4PBPA Vinyl Urethane Resin             --      56.5    --      256-EBPA DIMETHACRYLATE             --      --      45      45ETH. GYLCOL DIMETHACRYLATE             --      --      20      20VINYL TOLUENE (MONOMER)             --      --      10      10STYRENE (MONOMER) 43.9    43.5    --      --MOD L, 25% HQ (INHIBITOR)             0.15    0.15    0.08    0.08COBALT 12%, (PROMOTER)             0.30    0.30    0.30    0.30POTASSIUM 15%, (COPROMOTER)             0.20    0.20    0.20    0.20DMAA, (COPROMOTER)             0.30    0.30    0.30    0.30RESIN PROPERTIES (1)BRKFLD VISCOSITY @ 77 F., (CPS)             118     151     237     247RM. TEMP. (77 F.) GEL TIME: (MIN.)             25.0    24.0    19.0    22.8INTERVAL, (MINUTES)             19.1    16.7    3.3     4.6PEAK EXOTHERM, (F.)             282     291     284     293BARCOL HARDNESS-45 MINUTES        --      No Barcol Dev.                             42      461 HOUR            --      32      44      472 HOUR            --      31      45      453 HOUR            --      34      45      464 HOUR            --      36      45      4624 HOURS          --      36      46      481162 VOLATILE EMISSIONS, (G/M2)             32.7    25.4    8.5     4.8EMISSION TIME, (MINUTES)             35      37.5    7.7     8.0PHYSICAL PROPERTIES OFRESIN CLEAR CASTINGS: (1), (2)TENSILE STRENGTH, (PSI)             9,730 +/- 1,030                     8,570 +/- 1,710                             9,440 +/- 580                                     6,620 +/- 710TENSILE MODULUS, (MPSI)             0.555 +/- 0.039                     0.561 +/- 0.018                             0.497 +/- 0.020                                     0.503 +/- 0.020TENSILE ELONGATION, (%)             2.0 +/- 0.3                     1.7 +/- 0.4                             2.5 +/- 0.3                                     1.4 +/- 0.2FLEXURAL STRENGTH, (PSI)             20,380  16,200 +/- 2,830                             16,350 +/- 2,950                                     13,430 +/- 1,050FLEXURAL MODULUS, (MPSI)             0.526 +/- 0.003                     0.496 +/- 0.003                             0.456 +/- 0.102                                     0.446 +/- 0.004HEAT DISTORTION TEMP: DTUL, F.             190     205     179     182WATER ABSORPTION @ 150 F.24 HOURS:         0.39    0.46    0.85    0.917 DAYS:           0.67    0.73    1.32    1.38__________________________________________________________________________RESIN #           I-12    T-12    Y-12    Z-12__________________________________________________________________________COMPOSITION, %307-07 4PBPA Vinyl Urethane Resin             30      --      --      --307-33 4PBPA Vinyl Urethane Resin             --      45      42.9    --307-44 4PBPA Vinyl Urethane Resin             --      --      --      42.56-EBPA DIMETHACRYLATE             40      30      38.1    37.5ETH. GYLCOL DIMETHACRYLATE             20      15      9.5     10VINYL TOLUENE (MONOMER)             10      10      9.5     10STYRENE (MONOMER) --      --      --      --MOD L, 25% HQ (INHIBITOR)             0.05    0.03    0.06    0.08COBALT 12%, (PROMOTER)             0.30    0.30    0.30    0.30POTASSIUM 15%, (COPROMOTER)             0.20    0.20    0.20    0.20DMAA, (COPROMOTER)             0.30    0.30    0.30    0.30RESIN PROPERTIES (1)BRKFLD VISCOSITY @ 77 F., (CPS)             250     1,395   2,810   2,280RM. TEMP. (77 F.) GEL TIME: (MIN.)             20.5    21.0    16.5    30.0INTERVAL, (MINUTES)             6.3     5.1     4.5     5.4PEAK EXOTHERM, (F.)             282     280     264     273BARCOL HARDNESS-45 MINUTES        43      38      45      441 HOUR            43      44      46      452 HOUR            41      45      47      453 HOUR            41      45      47      474 HOUR            41      44      47      4824 HOURS          42      45      47      471162 VOLATILE EMISSIONS, (G/M2)             18.8    6.1-9.1 2.4     3.6EMISSION TIME, (MINUTES)             13.3    9.0     11      5.5PHYSICAL PROPERTIES OFRESIN CLEAR CASTINGS: (1), (2)TENSILE STRENGTH, (PSI)             7,600 +/- 1,030                     8,430 +/- 2,030                             9,660 +/- 1,370                                     9,150 +/- 1,280TENSILE MODULUS, (MPSI)             0.517 +/- 0.045                     0.562 +/- 0.008                             0.513 +/- 0.019                                     0.535 +/- 0.010TENSILE ELONGATION, (%)             1.7 +/- 0.3                     1.8 +/- 0.5                             2.6 +/- 0.8                                     2.0 +/- 0.4FLEXURAL STRENGTH, (PSI)             13,570 +/- 520                     18,340 +/- 1,340                             18,530 +/- 550                                     17,060 +/- 550FLEXURAL MODULUS, (MPSI)             0.476 +/- 0.006                     0.518 +/- 0.005                             0.481 +/- 0.005                                     0.462 +/- 0.004HEAT DISTORTION TEMP: DTUL, F.             170     163     221     171WATER ABSORPTION @ 150 F.24 HOURS:         0.71    0.68    0.92    0.797 DAYS:           1.26    1.26    1.46    1.38__________________________________________________________________________ (1)-1.5% HIPOINT 90 MEKP ROOM TEMPERATURE INITIATOR (2) 2 HOUR ROOM TEMPERATURE (77 F.) CURE, 2 HOUR POSTCURE @ 100 C. TOLUENE DIISOCYANATE WAS USED AS THE PREPOLYMER AND REACTED WITH THE MALEIC/DIESTER TO MAKE THE VINYL URETHANE RESIN 
    
     
                                           TABLE III__________________________________________________________________________LOE POLYMERS CONTAINING 4 PBPA URETHANE DIMETHACRYLATERESINS WITH SELECTIVE COMBINATIONS OF 6EBPA DIMETHACRYLATE,ETHYLENE GLYCOL DIMETHACRYLATE &amp; VINYLTOLUENE MONOMERS(MDI USED AS MONOMERIC BASE MATERIAL FOR URETHANE REACTION)RESIN #           E-13    F-13    G-13__________________________________________________________________________COMPOSITION ,%307-57 4PBPA Vinyl Urethane Resin             30      48.3    346-EBPA DIMETHACRYLATE             40      --      45ETH. GYLCOL DIMETHACRYLATE             20      --      11VINYL TOLUENE MONOMER             10      --      10STYRENE (MONOMER) --      51.7    --MOD L, 25% HQ (INHIBITOR)             0.03    0.09    0.04COBALT 12%, (PROMOTER)             0.30    0.30    0.30POTASSIUM 15%, (COPROMOTER)             0.20    0.20    0.20DMAA, (COPROMOTER)             0.30    0.30    0.30RESIN PROPERTIES (1)BRKFLD VISCOSITY @ 77 F., CPS             1450    990     3780RM. TEMP. 77 F. GEL TIME: (MIN.)             20      ˜20.0                             ˜23.0INTERVAL, (MINUTES)             3.6     --      --PEAK EXOTHERM, (F.)             271     --      --BARCOL HARDNESS-45 MINUTES        50      --      --1 HOUR            50      --      --2 HOUR            51      --      --3 HOUR            51      --      --4 HOUR            51      --      --24 HOURS          51      --      --1162 VOLATILE EMISSIONS, (G/M2)             13.9    23.6    6.1EMISSION TIME, (MINUTES)             7.0     109.0   7.0PHYSICAL PROPERTIES OFRESIN CLEAR CASTINGS: (1), (2)TENSILE STRENGTH, (PSI)             9,866 +/- 461                     11,062 +/- 318                             9,104 +/- 997TENSILE MODULUS, (MPSI)             0.486 +/- 0.011                     0.492 +/- 0.014                             0.492 +/- 0.011TENSILE ELONGATION, (%)             2.7 +/- 0.3                     3.4 +/- 0.5                             2.2 +/- 0.4FLEXURAL STRENGTH, (PSI)             17,867 +/- 373                     18,838 +/- 84                             17,461 +/- 474FLEXURAL MODULUS, (MPSI)             0.473 +/- 0.010                     0.460 +/- 0.004                             0.446 +/- 0.019HEAT DISTORTION TEMP: DTUL, F.             160     194     163WATER ABSORPTION @ 150 F.24 HOURS:         0.9     0.48    0.917 DAYS:           1.42    0.62    1.43__________________________________________________________________________ (1)-1.5% HIPOINT 90 MEKP ROOM TEMPERATURE INITIATOR (2) 2 HOUR ROOM TEMPERATURE (77 F.) CURE, 2 HOUR POSTCURE @ 100 C. METHYLENE DIISOCYANATE WAS USED AS THE PREPOLYMER AND REACTED WITH THE MALEIC/DIESTER TO MAKE THE VINYL URETHANE RESIN 
    
     
                                           TABLE IV__________________________________________________________________________LOE POLYMERS CONTAINING 4-EBPA URETHANE DIMETHACRYLATERESINS WITH SELECTIVE COMBINATIONS OF 6EBPA DIMETHACRYLATE,ETHYLENE GLYCOL DIMETHACRYLATE &amp; VINYLTOLUENE MONOMERS(IPDI USED AS MONOMERIC BASE MATERIAL FOR URETHANE REACTION)RESIN #           A-14    B-14    C-14    D-14__________________________________________________________________________COMPOSITION ,%307-94 4PBPA Vinyl Urethane Resin             60      30      40      506-EBPA DIMETHACRYLATE             --      40      30      30ETH. GYLCOL DIMETHACRYLATE             --      20      20      15VINYL TOLUENE (MONOMER)             --      10      10      5STYRENE (MONOMER) 40      --      --      --MOD L, 25% HQ (INHIBITOR)             0.14    0.12    0.12    0.14COBALT 12%, (PROMOTER)             0.30    0.30    0.30    0.30POTASSIUM 15%, (COPROMOTER)             0.20    0.20    0.20    0.20DMAA, (COPROMOTER)             0.30    0.30    0.30    0.30RESIN PROPERTIES (1)BRKFLD VISCOSITY @ 77 F., (CPS)             137     212     312     4760RM. TEMP. (77 F.) GEL TIME: (MIN.)             21      ˜20.0                             15      58INTERVAL, (MINUTES)             26.2    ˜3-4                             5.5     6.8PEAK EXOTHERM, (F.)             270     ˜280-290                             282     275BARCOL HARDNESS-45 MINUTES        No Barcol Dev.                     48      47      --1 HOUR            No Barcol Dev.                     50      48      --2 HOUR            No Barcol Dev.                     49      49      --3 HOUR            No Barcol Dev.                     49      50      --4 HOUR            8       50      50      --24 HOURS          14.4    51      52      --1162 VOLATILE EMISSIONS, (G/M2)             17      4.8     3       --EMISSION TIME, (MINUTES)             47      2       3.5     --PHYSICAL PROPERTIES OFRESIN CLEAR CASTINGS: (1), (2)TENSILE STRENGTH, (PSI)             8,810 +/- 680                     7,590 +/- 680                             6,290 +/- 1,000                                     6,010 +/- 1,380TENSILE MODULUS, (MPSI)             0.529 +/- 0.015                     0.527 +/- 0.077                             0.597 +/- 0.050                                     0.548 +/- 0.035TENSILE ELONGATION, (%)             1.9 +/- 0.2                     1.6 +/- 0.20                             1.2 +/- 0.20                                     1.2 +/- 0.40FLEXURAL STRENGTH, (PSI)             16,050 +/- 1,980                     15,636 +/- 860                             17,800 +/- 1,840                                     15,210 +/- 1,400FLEXURAL MODULUS, (MPSI)             0.474 +/- 0.010                     0.457 +/- 0.014                             0.520 +/- 0.071                                     0.487 +/- 0.006HEAT DISTORTION TEMP: DTUL, F.             171     160     160     142WATER ABSORPTION @ 150 F.24 HOURS:         0.66    1.09    0.97    1.247 DAYS:           1.1     1.58    1.55    1.86__________________________________________________________________________ (1)-1.5% HIPOINT 90 MEKP ROOM TEMPERATURE INITIATOR (2) 2 HOUR ROOM TEMPERATURE (77 F.) CURE, 2 HOUR POSTCURE @ 100 C. ISOPHORONE DIISOCYANATE WAS USED AS THE PREPOLYMER AND REACTED WITH THE MALEIC/DIESTER TO MAKE THE VINYL URETHANE RESIN 
    
     
                                           TABLE V__________________________________________________________________________LOE POLYMERS CONTAINING 4-PBPA URETHANE DIMETHACRYLATERESINS WITH SELECTIVE COMBINATIONS OF 6EBPA DIMETHACRYLATE,ETHYLENE GLYCOL DIMETHACRYLATE &amp; VINYLTOLUENE MONOMERS(DCHMDI USED AS MONOMERIC BASE MATERIAL FOR URETHANE REACTION)RESIN #            N-14     O-14     P-14    Q-14     R-14__________________________________________________________________________COMPOSITION, %307-1064PBPA Vinyl Urethane Resin              59       20       30      40       256-EBPA DIMETHACRYLATE              --       40       40      30       40ETH. GYLCOL DIMETHACRYLATE              --       20       20      20       20VINYL TOLUENE (MONOMER)              --       20       10      10       15STYRENE (MONOMER)  41       --       --      --       --MOD L, 25% HQ (INHIBITOR)              0.15     0.13     0.12    0.12     0.14COBALT 12%, (PROMOTER)              0.30     0.30     0.30    0.30     0.30POTASSIUM 15%, (COPROMOTER)              0.20     0.20     0.20    0.20     0.20DMAA, (COPROMOTER) 0.30     0.30     0.30    0.30     0.30RESIN PROPERTIES (1)BRKFLD VISCOSITY @ 77 F., (CPS)              165      61       258     660      ˜150RM. TEMP. (77 F.) FEL TIME: (MIN.)              21       17       15      18       ˜20-25INTERVAL, (MINUTES)              27       4.5      5.0     4.6      --PEAK EXOTHERM, (F.)              280      302      280     277      --BARCOL HARDNESS-45 MINUTES         No Barcol Dev.                       37       40      30       --1 HOUR             No Barcol Dev.                       43       45      45       --2 HOUR             No Barcol Dev.                       47       49      47       --3 HOUR             No Barcol Dev.                       --       --      --       --4 HOUR             No Barcol Dev.                       46       48      47       --24 HOURS           11       45       48      47       --1162 VOLATILE EMISSIONS, (G/M2)              15.7     24.2     6.1     4.8      --EMISSION TIME, (MINUTES)              45       4.0      5.0     4.0      --PHYSICAL PROPERTIES OF RESIN CLEAR CASTINGS: (1), (2)TENSILE STRENGTH, (PSI)              9,680 +/- 1,000                       8,830 +/- 820                                9,390 +/- 1,340                                        9,320 +/- 1,030                                                 7,050 +/- 1,360TENSILE MODULUS, (MPSI)              0.485 +/- 0.008                       0.454 +/- 0.020                                0.523 +/- 0.063                                        0.490 +/- 0.015                                                 0.446 +/- 0.012TENSILE ELONGATION, (%)              3.3 +/- 1.2                       2.4 +/- 0.5                                2.5 +/- 0.50                                        2.4 +/- 0.40                                                 1.8 +/- 0.40FLEXURAL STRENGTH, (PSI)              18,510   16,130 +/- 730                                16,310 +/- 320                                        16,520 +/-820                                                 13,730 +/- 1,220FLEXURAL MODULUS, (MPSI)              0.439 +/- 0.011                       0.412 +/- 0.002                                0.420 +/- 0.003                                        0.437 +/- 0.003                                                 0.380 +/- 0.003HEAT DISTORTION TEMP: DTUL, F.              177      180      165     160      175WATER ABSORPTION @ 150 F.24 HOURS:          0.54     1.04     1.11    1.00     0.917 DAYS:            0.84     1.34     1.55    1.54     1.36__________________________________________________________________________ (1)-1.5% HIPOINT 90 MEKP ROOM TEMPERATURE INITIATOR (2) 2 HOUR ROOM TEMPERATURE (77 F.) CURE, 2 HOUR POSTCURE @ 100 C. DICYCLOHEXYLMETHANE4,4, DIISOCYANATE WAS USED AS THE PREPOLYMER &amp; REACTED WITH THE MALEIC/DIESTER TO MAKE THE VINYL URETHANE RESIN