======Making Rayon Fiber======


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**Alternative titles:** Artificial Silk from Cotton
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====Summary====                   
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====Procedure====  
  - Prepare basic copper carbonate by reacting copper sulfate with baking soda, or use ready-made material.  
  - Place about 4 g of basic copper carbonate into a beaker.  
  - Add approximately 40 mL of concentrated ammonia solution (25%), forming a deep blue copper-ammonia complex.  
  - Filter or decant to remove undissolved residue.  
  - Gradually add ~1 g of cotton wool to the blue solution, stirring until it dissolves into a viscous liquid (viscose).  
  - Prepare a 1 M sulfuric acid solution in a separate beaker.  
  - Fill a syringe with viscose and slowly inject it into the sulfuric acid.  
  - Observe as fine rayon fibers form, initially blue, then turning colorless as the copper salts are removed by the acid.  
  - Collect the fibers and examine their texture.



====Links==== 
Making Rayon Fiber - Artificial silk, chemical experiment - Thoisoi2 - Chemical Experiments!: 
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Schweitzer Reagent : Making Rayon DIY demo - vibzz lab: 
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====Variations====
  * Try different extrusion methods (needle size, pouring, or pipette).  
  * Compare rayon fibers with natural silk or nylon fibers to discuss properties.



====Safety Precautions====
  * Perform in a fume hood or well-ventilated area due to ammonia vapors.  
  * Wear chemical-resistant gloves, safety glasses, and a lab coat.  
  * Ammonia solution is corrosive and releases harmful fumes.  
  * Copper compounds are toxic; avoid ingestion or skin contact.  
  * Sulfuric acid (1 M) is corrosive; handle with care and rinse spills immediately.  
  * Dispose of copper-containing waste properly as hazardous chemical waste.




====Questions to Consider====
  * What role does the copper-ammonia complex play in dissolving cotton? (It forms Schweizer’s reagent, which can dissolve cellulose.)  
  * Why does sulfuric acid cause fibers to reappear? (The acid breaks down the copper complex and precipitates cellulose as solid fibers.)  
  * How does rayon compare to natural silk in strength and softness?  
  * What are some advantages and disadvantages of artificial fibers compared to natural ones?