Polyether polyurethanes

This paper describes a method for improving hydrophilicity by using radiation-induced grafting of flexible polyurethane (polyether) foam with polar vinyl monomers. By this procedure, the normally hydrophobic material can be converted into a remarkably water-wettable sponge. 

Materials. The flexible polyurethane (polyether) foam, formulated from a polyol, tolylene diisocyanate, emulsifier, catalyst, and blowing agent, was obtained from the Nopco Chemical Co. It had a density of about 1.5 pounds per cubic foot (0.02 gram per cc.) and contained approximately 40 open cells per linear inch. The foam samples were washed in detergent, dried, and weighed before being irradiated. 

Oligomeric carbodiimides are efficient stabilizers for polyester, polyester based polyurethanes, polyether based polyurethanes and polyether based poly(urethane ureas). Oligomeric carbodiimides are commercially available under the trade name Stabaxol from Rhein Chemie, a subsidiary of Bayer. 

The Mesogenic Index has been applied to a substantial body of data on polyesters and polyamides drawn from from published literature including 22 systems where the critical concentration for onset of liquid crystallinity has been established with reasonable accuracy (Tables 2 and 3). The characteristic value of the MI at the onset of a liquid crystalline phase is generally found to be remarkably close to 10. When applied to the more limited data available on polyurethanes, polyethers, polycarbonates, the rule holds up well. 

Step-Growth Polymerization Polyurethanes, Polyether-esters, Polyamides... 

E15LV Methocel J5MS Natrosol 250 ER Natrosol 250 GR Natrosol 250 H4R Natrosol 250 HBR Natrosol 250 HHR Natrosol 250 HR Natrosol 250 JR Natrosol 250 KR Natrosol 250 LR Natrosol 250 MHR Natrosol 250 MR Natrosol B Natrosol FPS Opilflo M210 Polyurethane, polyether tNckener, latex systems Carbopol EP-1 Carbopol EP-2 tNckener, latex-based architectural paints Min-U-Gel 400 Min-U-Gel 500 Min-U-Gel PC... 

Polyurethane Polyether-urethane FTIR or UV spectroscopy Aspergillus niger and [124]... 

TYPICAL PROCESSING TEMPERATURES FOR POLYURETHANE POLYETHER RUBBER... 

This methodology is quite general and can be utilized to prepare several types of polymers such as polyamides, polyimides, polyurethanes, polyethers etc. The polymer properties depend on the type of functional groups that link the polymer building blocks. Further modulation is achievable by varying the nature of the difimctional monomer within each class of polymers. It is not always necessary to condense two difunctional monomers. Some polymers such as polyethers are prepared by the oxidative coupling of the corresponding phenols. A few examples of polymers that can be prepared by the condensation reactions are shown in Fig. 1.2. 

MORTHANE" (Morton International) PELLETHANE" (Dow) ELASTOLLAN (BASF) DESMOPAN and TEXIN (Bayer) J Polyurethane Polyether or amorphous polyester Hard and Tough. Abrasion and oil resistant. Good tear strength... 

Vinyl ethers (VE) are amongst the most reactive monomers that polymerise cationically, and they are increasingly used in photocurable resins, either neat [63] or in association with epoxides [64,65], acrylates [66], maleimides [67] or unsaturated polyesters [68]. Vinyl ether end-capped polyurethane, polyether, polysiloxane and polyesters were shown to undergo fast and extensive polymerisation when exposed to UV-radiation in the presence of an aryliodonium salt, with the formation of tridimensional polymer networks. The photoinitiated catioiuc polymerisation of a divinyl ether can be formally written as follows ... 

Determination of the content of oxyethylene groups in ethylene oxide-propylene oxide can also easily be carried out by NMR spectrometry without chemical splitting of the ether linkage, identifying the base compounds by this method is difficult. Several methods for the cleavage of ethers have been studied, but few applied to the identification of the base compounds of the polyurethane polyethers. 

J. L. Illinger, N. S. Schneider and F. E. Karasz, "Low Temperature Dynamic Mechanical Properties of Polyurethane-Polyether Block Copolymers", Poly. Eng. Sci. 1, 25 (1972). 

Figure 3.9 Reaction of polyethers with p-toluene sulfonic acid - gas chromatography. Gas chromatogram of reaction products of polyurethane polyethers (1) propylene glycol diacetate (2) glycerol triacetate (3) trimethylpropane triacetate (4) triethylanolamine triacetate (5) pentaerythritol tetracetate. Gas chromatographic conditions column 1 m x 3 mm, coated with 15% FFAQ on Uniport B, oven 170 °C chart speed 1 cm/s. (b) Gas chromatogram of reaction products of polyurethane polyethers based on amines (1) pyropylene glycol diacetate (2) derivative from 1,2 diaminoethane (3) derivative from 2,2 -diaminodiethylamine. Gas chromatographic conditions Column 1 m x 3 mm packed with 15% SE-30 on Uniport B oven 230 "C chart speed, 1 cm/min.

PELLETHANE Polyurethane Polyether or amorphous polyester Hard and tough. Abrasion and oil resistant. Good tear strength... 

A typical formulation of a photocurable composite resin contains four basic components a radical-type photo initiator, an acrylate functionalized oligomer, a reactive diluent and the clay mineral filler. The photoinitiator is usually an aromatic ketone which cleaves into two radical fragments upon UV exposure. The telechelic oligomer consists of a short polymer chain (polyurethane, polyether, polyester) end-capped by the very reactive acrylate double bond. An acrylate monomer is generally used as reactive diluent to reduce the resin viscosity. Figure 7.2 shows some typical compounds used in UV-curable acrylic resins. Different types of phyllosilicates were selected as mineral filler an organophilic clay (Nanomer I-30E from Nanocor), native hydrophilic clays (montmorillonite KIO and bentonite) and a synthetic clay (beidellite). 

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