Scenario: An engineer at an injection molding manufacturer needs to identify a suitable resin for injection molding of a screw cap vial. To meet the design specification, the resin used must have a water vapor transmission rate lower than .17 g mm/m2/day. Knovel can help.
- On the Knovel home page click on the "Advanced Search" button at the top right of the screen. For the first search criteria select permeability in the "Category" drop down list. When you select it, the value vapor transmission rate automatically appears in "Field Name," and g mm/(m^2 day) automatically appears in "Units," keep those default selections. In the Operator drop down box, select less than or equal to (<=). In the Numeric Value box enter a value of .17. For the second search criteria leave "Category" as keyword (default), and in the "Keyword(s)" box enter the word water. Click the "Search" button at the bottom of the screen.
- The search results page shows one title that matches the "search" query, Permeability and Other Film Properties of Plastics and Elastomers, which is this issue's Featured Title. Click on the name.
- The Table of Contents appears. Only chapters or sections where there are hits from the "search" query will show by default. The very first section looks interesting: "Permeability Properties - Thermoplastic, Polyethylene, HDPE." Click on the Table (5) link next to it.
- A new window opens launching a Knovel Interactive Table and displaying five rows of the table. It looks like the material "Thermoplastic, Polyethylene, HDPE," which goes by various trade names, will do nicely for the injection molding application. Each row of the table shows the material subjected to water vapor at different temperatures. In each case, the water vapor transmission rate stays below the required .17 g mm/m2/day.
