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Copyright (c) 2006-2014 MindTouch Inc.
This file and accompanying files are licensed under the MindTouch Master Subscription Agreement (MSA).
At any time, you shall not, directly or indirectly: (i) sublicense, resell, rent, lease, distribute, market, commercialize or otherwise transfer rights or usage to: (a) the Software, (b) any modified version or derivative work of the Software created by you or for you, or (c) MindTouch Open Source (which includes all non-supported versions of MindTouch-developed software), for any purpose including timesharing or service bureau purposes; (ii) remove or alter any copyright, trademark or proprietary notice in the Software; (iii) transfer, use or export the Software in violation of any applicable laws or regulations of any government or governmental agency; (iv) use or run on any of your hardware, or have deployed for use, any production version of MindTouch Open Source; (v) use any of the Support Services, Error corrections, Updates or Upgrades, for the MindTouch Open Source software or for any Server for which Support Services are not then purchased as provided hereunder; or (vi) reverse engineer, decompile or modify any encrypted or encoded portion of the Software.
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|Formaldehyde is added to the beaker inside a fume hood. |
Aniline hydrochloride (C6H5NH3Cl) is rapidly added.
The polymer expands out of the beaker, along with a prodigious amount of heat.
This reaction is highly exothermic, but that is not why the plastic produced is referred to as "thermoset".
Bakelite is a space-network polymer. Unlike linear and branched polymers, which are composed of long molecules that make them more or less crystalline, space-network polymers are highly and irregularly cross-linked throughout the structure. The sheer extent of the cross-linking means that a sample of the material is essentially one gigantic molecule.
Although heat softens and melts linear and branched polymers, heating does not soften space-network polymers because such a softening would require the breaking of covalent bonds. In fact, heating usually produces additional cross-linking in these polymers, making them harder. It is for this reason that space-network polymers, such as bakelite, are called thermoset plastics.
An NSF funded Project