Patent ID: 12187836

EXAMPLES

TABLE 1Substances usedVoranolVoranol ® CP 4755 (Dow Chemical); polyether triol,CP 4755CAS No. 9082-00-2; MW: 5000 g/mol; OH value: 35 mgKOH/gAcclaimAcclaim ® Polyol 4200 (Covestro); polyether diol,4200Mn: approx. 4000 g/mol; OH number: 26.5-29.5 mg KOH/gEthacureEthacure ® 300 (Albemarle); 6-methyl-2,4-bis(methylthio)phenylene-1,3-diamine (amine crosslinker)Pentane-(Sigma Aldrich)1,5-diolDIDPJayflex ® DIDP (ExxonMobil Chemical); diisodecylphthalate (plasticizer)ThiocureThiocure ® GDMP (Bruno Bock Thiochemicals); glycolGDMPdi(3-mercaptopropionate)DesmodurDesmodur ® CD-L (Covestro); modified diphenylmethaneCD-L4,4′-diisocyanate (MDI); NCO content: 29.5% by weightMonarchMonarch ® 570 (Cabot Corp.); carbon black (filler)570Omya BLOmya ® BL (Omya); ground, natural chalk (filler)Bi cat.35% by weight of Coscat 83 (organobismuth catalyst;(2.68 mmolCoscat ® 83 (Vertellus Specialties Inc.)) in plasticizerBi/g)containing 1 molar equivalent of 8-hydroxyquinoline(based on Bi)Sn cat.dibutyltin dilaurate (Sigma Aldrich)
Production of Polyurethane Compositions

For each composition, the ingredients of the first component A specified in table 2 were processed in the amounts specified (in parts by weight or % by weight), by means of a vacuum dissolver with the exclusion of moisture, to give a homogeneous paste and stored. The ingredients of the second component B specified in the tables were likewise processed and stored. The two components were then processed for 30 seconds, by means of a SpeedMixer® (DAC 150 FV, Hauschild), into a homogeneous paste, which was immediately tested as follows:

For determination of the mechanical properties, the compositions were cured at 23° C. and 50% RH for 7 days, and modulus of elasticity (“MoE”) in the range from 0.5% to 5% elongation and 0.05% to 0.25% elongation, tensile strength and elongation at break of the test specimens thus produced were measured according to DIN EN ISO 527 on a Zwick Z020 tensile tester at 23° C. and 50% RH and a testing speed of 10 mm/min.

Shore A hardness was determined to DIN 53505 on test specimens having a layer thickness of 6 mm that had been cured at 23° C. and 50% relative humidity. The exact storage time (curing time) before the respective measurement is specified in table 3.

Tg values (glass transition temperatures) were determined using a Rheoplus MCR 302 instrument from Anton Paar on the basis of DMA measurements on cuboidal samples (43.515 mm×10 mm×1.49 mm), which were cured for 7 days under standard climatic conditions (“SCC”; 23° C., 50% relative humidity “RH”). The measurement conditions were: measurement in shear mode, excitation frequency 1 Hz, and heating rate of 5 K/min. The samples were cooled to −100° C. and heated to 100° C. with determination of the complex shear modulus G* [MPa], by reading off a maximum in the curve for the loss angle “tan 6” as the Tg value.

Pot life was measured in a viscometer as the time until the viscosity was 500 Pa·s after the two components had been mixed. Viscosity was measured on an MCR 302 parallel-plate rheometer (Anton Paar) with a plate diameter of 25 mm and a plate distance of 1 mm at a frequency of 0.1 s−1and a temperature of 20° C. This was done by first mixing the two components for 30 sec in a Speedmixer (Hauschild) and immediately applying the mixture to the plates for the measurement.

Viscosity was measured on an MCR 302 parallel-plate rheometer (Anton Paar) with a plate diameter of 25 mm and a plate distance of 1 mm at a frequency of 0.01 s−1, 1 s−1and 10 s−1and a temperature of 20° C. This was done by first mixing the two components for 30 sec in a Speedmixer (Hauschild) and immediately applying the mixture to the plates for the measurement.

TABLE 2Example compositions producedExampleC-1 (Ref.)C-2First component A (amounts in parts by weight)Voranol CP 47552728Acclaim 42002728Ethacure7—Pentane-1,5-diol—4.5Omya BL20.9528Monarch 57011DIDP178.7Bi cat. (2.68 mmol Bi/g)—0.1Sn cat.0.05—Thiocure GDMP—1.7TOTAL100100Second component B (amounts in parts by weight)Desmodur CD-L100100TOTAL100100Mixture of A and BMixing ratio (volume)100:15100:15of A:BMolar ratio of SH:Bi—53:1

TABLE 3Measurement values for the example compositionsMeasurementC-1 (Ref.)C-2Tg [° C.]−57.64−36.71Pot life [min]1055Shore A (after 1 h)3149Shore A (after 2 h)3654Shore A (after 4 h)6257Shore A (after 24 h)6760Shore A (after 7 d)7060Tensile strength [MPa]2.532.42Elongation at break [%]105.8139.1MoE 0.05-0.25% [MPa]12.511.5MoE 0.5-5% [MPa]9.28.6Viscosity (freshly mixed) [Pa · s] (0.01 s−1)45.83070Viscosity (freshly mixed) [Pa · s] (1 s−1)15103Viscosity (freshly mixed) [Pa · s] (10 s−1)8.2321.1

The results in table 3 show that the mechanical values of the two compositions after complete curing and the Tg values are comparable. Distinct differences arise in the pot life, which is much higher in the inventive example than in the reference example. In addition, the inventive example reaches the final values for Shore A hardness much more quickly. The viscosities of the two compositions show suitability as casting compound.

TABLE 4Evolution of viscosity of the example compositions (0.1 s−1)TimeC-1 (Ref.)C-2(min after mixing)(viscosity in Pa · s)(viscosity in Pa · s)124.67130.2596.5314610493.615420497116730146101864026 5602175039 220292.66051 8308 6807064 070107 7008075 770213 9009086 880284 400

Table 4 compares the evolution of viscosity (shear rate 0.1 s−1) over time for the two compositions. It is clearly apparent that the inventive example has almost constantly low viscosity over a long period of time (pot life), but then very rapidly gains viscosity when the curing reaction begins to start up. The comparative example, by contrast, shows a viscosity that rises gradually from the start, but is then overtaken by the inventive example. Thus, in the inventive example, processibility during the pot life is improved (constant viscosity), but curing is then very much more rapid than in the reference example.