 Process for preparing biaxially oriented polypropylene film suitable for twist wrapping |
| It is therefore an object of the instant invention to provide a multilayered, coextruded, highly ... |
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| Process for the production of a biaxially highly oriented polypropylene film |
| The propylene polymer of the base ply (or single ply, if there are no top plies) is preferably ... |
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| Process for making a drag shield for a power mower |
| With the problems of the prior art in mind, the present invention includes two opposing and spaced ... |
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| Process for producing a chloromethylated polymer |
| We claim: 1. A process for producing a chloromethylated polymer by reacting styrene polymer ... |
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| Method of polymerizing vinyl halide with olefin polymers and copolymers and compositions thereof |
| What is claimed is: 1. In a process for the preparation of a vinyl chloride polymer comprising ... |
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| Method of preparing vinyl halide polymers and copolymers with polyolefins |
| OF THE INVENTION AND PREFERRED EMBODIMENTS THEREOF Except for the above-defined improvements of ... |
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| Ceramic tile adhesive water resistant compositions based on copolymers emulsions |
| I claim: 1. A ceramic tile adhesive composition containing from 20 to 90% by weight of the total ... |
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| Thermoplastic molding materials based on polyamide blends |
| We claim: 1. A thermoplastic molding material containing, as essential components, A) 20-98% by ... |
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| Use of thermoplastic elastomers for improving the stability of polyolefins to ionizing radiation |
| What is claimed is: 1. A method for improving the stability of a polyolefin base polymer to ... |
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Surface wettable silicone hydrogels
| Details |
Inventors: Lai, Yu-Chin; Ruscio, Dominic V.; Valint, Jr., Paul L.;
Assignee: Bausch & Lomb Incorporated (Rochester, NY)
Primary Examiner: Lipman; Bernard
Assistant Examiner:
Attorney, Agent or Firm: Krasnow; David M.
A novel silicone-containing, hydrogel material is disclosed comprising an acrylic-capped polysiloxane prepolymer, polymerized with a bulky polysiloxanylalkyl (meth)acrylate monomer and at least one hydrophilic monomer. |
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DETAILED DESCRIPTION OF THE INVENTION The crosslinked polymeric network found in the hydrogels of the present invention are believed to be formed, in part, from the polysiloxane prepolymer .
alpha.
,.
omega.
bonded through a divalent hydrocarbon group to a polymerized activated unsaturated group.
When the term "activated" is used with the term "unsaturated group" herein, it is meant that an unsaturated group which is activated is one which has a substituent which facilitates free radical polymerization.
These activated unsaturated groups are polymerized to form the polymers of the present invention.
Preferably the activating groups lend themselves to polymerization under mild conditions, such as, ambient temperatures.
Notations such as "(meth)acrylate" or "(meth) acrylamide" are used herein to denote optional methyl substitution.
Thus, for example, methyl (meth)acrylate includes both methyl acrylate and methyl methacrylate and N-alkyl(meth)acrylamide includes both N-alkyl acrylamide and N-alkyl methacrylamide.
The term "prepolymer" denotes a high molecular weight monomer containing at least two polymerizable groups.
Polymerization of prepolymers with other monomers as described herein produces polymers having a crosslinked, three dimensional network which can be used to produce wettable hydrogels with good rigidity, oxygen permeability and other physical properties.
These silicone-containing hydrogels are well-suited for use as biomedical devices such as contact lenses.
The present invention contemplates polymerizing acrylic-capped polysiloxane prepolymers with bulky polysiloxanylalkyl (meth)acrylate monomers and at least one hydrophilic monomer.
Preferred acrylic-capped polysiloxane prepolymers of the present invention are those having from about 2 to about 200 repeating dimethylsiloxane units, such as .
alpha.
,.
omega.
-Bis(methacryloxyalkyl) polysiloxane, and is most preferably .
alpha.
,.
omega.
-Bis(methacryloxybutyl)dimethylsilyl polysiloxane which has about 25 repeating dimethylsiloxane units such that, in Formula I, m+n+p is equal to about 25
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Adhesives and Rubbers 
