======Making Bakelite======


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**Alternative titles:** Phenol-Formaldehyde Condensation Polymer
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====Summary====                   
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====Procedure====  
  * See links below for full method.



====Links==== 
Making Bakelite - Periodic Table of Videos - Periodic Videos: 
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Making World's First Plastic - Prussian Blue: 
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====Variations====
  * None



====Safety Precautions====
  * Work in a fume hood; formaldehyde is toxic and a probable carcinogen, and phenol is highly corrosive and readily absorbed through skin.  
  * Wear splash goggles, face shield for pouring, lab coat, and chemical-resistant gloves rated for phenol and formaldehyde; change gloves immediately if contaminated.  
  * Control heating; the reaction can exotherm and foam. Use small batches, a thermometer, and a heat shield.  
  * Keep ignition sources away from flammable solvents or vapors that may be present.  
  * Hot molds and resin can cause burns; handle with heat-resistant gloves and allow full cooling before opening.  
  * Avoid creating dust when cutting or sanding cured parts; use local exhaust and a particulate mask if machining.  
  * Collect phenol and formaldehyde containing wastes in labeled hazardous waste containers for proper disposal.





====Questions to Consider====
  * What type of polymerization forms bakelite? (Condensation polymerization producing water as a by-product during crosslinking)  
  * Why does the resin turn from clear to opaque during curing? (Growing molecular weight and crosslink density cause phase changes and light scattering)  
  * How does a thermoset differ from a thermoplastic upon reheating? (Thermosets do not melt; their covalent crosslinks prevent flow, while thermoplastics soften and can be remolded)  
  * What is the role of the catalyst in this synthesis? (It accelerates formation of methylene and ether bridges between phenol rings, controlling resin type and cure rate)  
  * Why are fillers often added to phenolic resins? (They improve toughness, dimensional stability, machinability, and reduce shrinkage and cost)