Dibutyltin dilaurate catalyst

Liquid poly(caprolactone) triol — 540 MW Dibutyltin dilaurate catalyst — 0.001% by weight... 

PSA Formulation and Properties. The formulations used in this study for the Hycar 2103-Prepolymer C and Hycar 2106-Prepolymer C PSA contain OH/NCO ratios of 1.7 and 1.3, respectively. Dibutyltin dilaurate catalyst is used at a 0.2 wt.% level based on the total adhesive solids. PSA samples are made from an 80% solids solution (by wt.) with a dry solvent system (27/73 by wt. of ethyl acetate-toluene) and cured at 150°C for 45 seconds. The samples are then evaluated by running 180° peel, static shear, rolling ball tack, and vinyl film shrinkage tests. 

The IPNs prepared were composed of a rubbery polyurethane and a glassy epoxy component. For the polyurethane portion, a carbodiimide-modified diphenyl-methane diisocyanate (Isonate 143L) was used with a polycaprolactone glycol (TONE polyol 0230) and a dibutyltin dilaurate catalyst (T-12). For the epoxy, a bisphenol-A epichlorohydrin (DER 330) was used with a Lewis acid catalyst system (BF -etherate). The catalysts crosslink via a ring-opening mechanism and were intentionally selected to provide minimum grafting with any of the polyurethane components. The urethane/epoxy ratio was maintained constant at 50/50. A number of fillers were included in the IPN formulations. The materials used are shown in Table I. 

Richter and Macsoko (1980) describe the chemoviscosity of a reactive polyurethane (4,4 -diphenyl methane diisocyanate, polyester triol and dibutyltin dilaurate catalyst) reasonably well by the following model ... 

PC (90-70) / PCE (10-30) internal mixer or SSE at 240-250°C / DSC / selective solvent extraction / FTIR / rheology / toluene sulfonic acid (0.1-2) or Ti(OBu) or dibutyltin dilaurate catalyst / other catalysts ineffective Shuster et al., 1994... 

Tetrasodium EDTA Trisodium EDTA catalyst, sealants Triethylene diamine catalyst, shoe soles Diazabicycloundecene catalyst, SHOP process Nickel chloride hexahydrate catalyst, silicone elastomers Dibutyltin dilaurate catalyst, silicone rubber curing Bis (2,4-dichlorobenzoyl) peroxide catalyst, silicone rubber 2-component Chloroplatinic acid catalyst, slabstock N,N,N -Trimethyl-N -hydroxyethylbisaminoethylether catalyst, SO2 oxidation Cesium sulfate catalyst, solder fluxes Isooctyl acid phosphate catalyst, soldering fluxes Ethyl acid phosphate 2-Ethylhexyl phosphate Stearyl acid phosphate catalyst, solid fuels Ferric acetylacetonate catalyst, solid rocket fuels Copper nitrate (ic) catalyst, solvent extractants Ethyl acid phosphate 2-Ethylhexyl phosphate Stearyl acid phosphate catalyst, solvent hydrogenation beer-making hops... 

CD-MDI, polyol and BDO were charged to a 250 ml glass jar. Dibutyltin dilaurate catalyst (25-50 ppm) was added to adjust the pot life to approximately 90 seconds. These components were mixed thoroughly and poured into preheated moulds at 100 °C, treated with mould release. After demoulding, the samples were post-cured at 100 °C for 16 hours. The polymer samples were conditioned at 23 °C and 50% relative humidity for at least four weeks prior to testing. 

PET (100-90)/LCP (0-10) (Unitika LC3000) TSE at 290 °C/DSC/SEM/capillary rheometry/WAXD/NMR/fiber tensile properties/dibutyltin dilaurate catalyst (0-0.1 wt%) Hong et al. 1997... 

Diol-2 and Diol-3 were conveniently synthesized by reacting MDI (0.9 mmole) with excess Diol-1 (3.6 mmole) in 180 ml toluene in the gresence of dibutyltin dilaurate catalyst (0.001-0.1 mmole) at 90 u for 2 h (Figure 6). After evaporation of the solvent, unreacted Diol-1 was removed from the residue by repeated extraction with cold methanol (ca. 0.6 g pure Diol-1 recoverable) the remaining residue was boiled with methanol. 

Fig. 21. GPC trace of the segmented PU elastomer PU-4 with monodisperse hard segment length distribution (cf, reaction scheme Fig. 10) before (—) and after heating in DMA solution (1 weight % PU-4) at 75 C in the presence of dibutyltin dilaurate catalyst (0.15 weight %) for 2 hr ( ) and 4 or 6 hr ((------------)/ identical chromatograms).

Siloxane Functionalization of Tone Polyols. Tone polyols were siloxane functionalized by reaction with tetraethyl orthosilicate in refluxing xylene in presence of dibutyltin dilaurate catalyst. We have reported details of this procedure in an earlier communication (Wu, S. and Soucek, M.D., Polym. Commun., in press). 

Tone polyols were siloxane functionalized by reacting with tetraethyl orthosilicate in presence of dibutyltin dilaurate catalyst. The synthesized siloxane functionalized polyols did not undergo self-condensation when exposed to UV radiation in presence of photoacid generators. However, the combination of siloxane functionalized polyols and cycloaliphatic diepoxides formed cohesive crosslinked films. Partial replacement of polyols with the siloxane modified polyols enhanced adhesion of the... 

Polyurethane-based formulations were processed by another way. Nanoclays were mechanically dispersed in the polyol (PBHT) in a vessel with a mechanical stirrer. Three drops of dibutyltin dilaurate (catalyst) and MDI was then added. The ratio diisocyanate/polyol was set at 1.1 because previous studies that we realized showed that it was the best compromise for low modulus and high elongation at break, (the polyurethane alone is called PUl.l). The mix was heated in an oven at 80°C in order to melt MDI, afterwards the mix was sheet-shaped in a thermocompression press at... 

Solution Polymerization. Fluorinated diols lb and Ic react with hexamethylene diisocyanate in THF in the presence of dibutyltin dilaurate catalyst to give polyurethanes having structures 4 and 6 (Scheme 1). In a typical synthesis, 1.7 X 10 mol of dibutyltin dilaurate was added to a solution of 1.91 X 10 mol of hexamethylene diisocyanate (HDI, 2) in 0.5 mL of THF. A solution of 1.250 g of Ic in 1.5 niL of THF was then added. The solution was stirred for 2 hours at 25 C, after which time the solution was very viscous. THF (22 mL) was added and the mixture was heated at 68 C. The soluble fraction was decanted from the insoluble fraction. The soluble fraction was poured into 500 mL of methanol, yielding a white precipitate. After... 

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