Browse Prior Art Database

Reduced R-Value Loss in Polymeric Foams Disclosure Number: IPCOM000245299D
Publication Date: 2016-Feb-26
Document File: 4 page(s) / 223K

Publishing Venue

The Prior Art Database


Disclosed is a method to generate a reduced r-value loss polymeric foam. Also presented are methods to generate gas-filled glass spheres and gas-filled polymeric capsules.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 40% of the total text.

Page 01 of 4

Reduced R-Value Loss in Polymeric Foams

Recently, Open Innovation was seeking approaches to reduce R-value loss in polymeric foams .[1] "R-value is the measurement of thermal resistance; the higher the number, the more efficient".[2] When polyurethane or polyisocyanurate foams are made, the reaction is exothermic which causes cell gasses to also cool during closed cell foam manufacturing. As the cell gasses cool, the gas is condensed and creates a partial vacuum in these cell thus pulling air into them. The result is a reduced thermal performance foam with losses in K-factor ratings. Additionally, "In most cases, the gasses are also soluble in the polymer matrix to varying degrees, which further contributes to the loss of the desired blowing agent in the cells."[1] These foams also "exhibit an aging effect in which thermal insulation performance decreases over time."

Here we present a method to reduce R-value loss in polymeric foams using r-value increasers to create a new closed cell foam material. The core idea of the invention is as follows: A two part foam resin system is used to generate a polymeric foam. The resin system also includes a blowing agent, a filler material, and a surrounding atmosphere that will all increase the r-value of a polymeric foam.

The invention works as follows: A two part foam resin system is used to generate a polymeric foam material. One part contains a glass sphere and/or a polymeric microcapsule that contains and inert gas. The two parts of the resin are combined together with a blowing agent and sprayed into a foam material. Here, the blowing agent rather than air or CO2 is an inert gas such as argon. As the the foam is blown, the inert gas gets trapped in the cells of the foamed material. To further aid this process, the foam is sprayed in a surrounding atmosphere that is an inert gas such as argon. As the gasses in the cells cool, argon is drawn into the closed cell foam. Since air is not present due to the argon in the blown agent and the surrounding atmosphere, argon will be the only gas drawn in by the vacuum that is created. As mentioned above, glass microspheres and/or polymeric microcapsules can be used in the formulation to aid in the reduced r-value loss.

Glass microspheres containing argon can be produced as follows:

As shown in the art [3], hollow glass microspheres can be produced using a torch flame, and irregular glass frit, and a vibrating spatula. This method is generally referred to as the flame spraying method (Figure 1). Here, we modify this approach by placing the setup in an argon atmosphere. Since argon is a non-flammable and non-toxic gas, the injection of the argon gas into the surrounding atmosphere and the stream of the torch allows it to be captured inside the glass microspheres thus making them gas-filled glass microspheres that can be blended with the resin. In another embodiment, the surface of the glass microspheres can be surface modified to incorporate a plethor...