Towel origami

I have been folding towel animals for Hilton Friends and Family visitors. I like them to think our hotel is a little better than theirs.

Borax Slime

Elmers (white school) Glue is a polyvinyl acetate (C₄H₆O₂)_n. The glue is sensitive to base hydrolysis (the cleavage of chemical bonds by the addition of water) and will slowly convert PVAc into polyvinyl alcohol (the gluey part) and acetic acid (vinegar).  The glue reacts with water to some extent to replace some of the acetate groups with OH (alcohol) groups.Under alkaline conditions, boron compounds such as boric acid or borax cause the polymer to cross-link, forming tackifying precipitates or toys such as Slime and Flubber.  The B-OH groups on the borax molecules react with the acetate groups on the glue molecules (relatively long polymer chains) to eliminate acetic acid and form new bonds between the borax and two glue molecules. The linking of two glue molecules via one borax molecule is called polymer cross-linking and it makes a bigger polymer molecule, which is now less liquid-like and more solid.  If you don’t add enough borax  there may not be enough borax present to fully polymerize the glue molecules. This will lead to a very gooey, slime-like product. The thickening observed is a result of hydrogen bonding between the molecules



Borax                                    +            Glue                              =            Polymer Slime

Salt and Laundry

Last Friday I made the claim that baking soda is a poor replacement for Super Wash Soda, and is not necessary to add to the laundry detergent because I don't have hard water.  But what about people who do have hard water?  Hard water contains dissolved calcium and magnesium.  It can precipitate out of hard water as scale, which builds up on the insides of your washing machine (and tea kettle and everything else), and hard water reduces soap's ability to lather, whether in the shower, sink, dishwasher or washing machine, and reacts with soap to form a sticky scum.  You can combat hard water in various ways, including filtering it by distillation or reverse osmosis, adding  powdered borax or washing soda (already contained in our home made detergent), or running it through a water softener (which implies salted water).  What if we just add salt to the laundry detergent mix?
All over the internet you can find recipes for homemade fabric softener crystals using kosher salt and Epsom salts, but these two items are not interchangeable.  Epsom salt is magnesium sulfate (MgSO₄ + 7H2O).  Hard water is caused by calcium and magnesium.  So by adding Epsom salt to your laundry you are making  your hard water even harder.  Hard water causes soap to be less effective, fades colors, and causes fabric to feel rough and scratchy.  Kosher salt (sodium chloride) is NaCl.  When dissolved in water, the sodium chloride framework disintegrates as the Na⁺ and Cl⁻ ions become surrounded by the polar water molecules.  It makes your detergent work even harder. Salt is proven effective against blood, gravy, grease, ink, and wine. It is also great at getting out set in stains. And what is even cheaper than Kosher salt? Regular table salt (it's just crushed into a different size flake).  Adding table salt to your home made detergent is the way to go if you have hard water! If you don't have hard water, you may still consider salt as a stain pretreatment.

Vinegar And Laundry

The internet claim:  "Just adding 1/2 cup vinegar to the final rinse will result in brighter, clearer colors and fluffier laundry"

The science: CH3COOH + H20 --> CH3COO- + H3O+
vinegar (acetic acid) + water --> acetate ion (which is a very weak acid) + Hydronium ion
The acidic solution is supposed to dissolve soap reside (alkalies) left by soaps and detergents allowing the laundry fibers to because more absorbent and fluffy.

An ion is a charged atom or molecule. It is charged because the number of electrons do not equal the number of protons in the atom or molecule. An atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.
Warning: Never combine vinegar with chlorine bleach as this will result in harmful fumes. Do not use vinegar on silk, acetate, or rayon clothing. 

My claim: Adding vinegar to laundry is redundant and will not cut laundry costs if you are using home made detergent.  In the following reaction, I assume the baking soda is coming from your home made detergent.

The science: NaHCO₃ + HC₂H₃O₂ → NaC₂H₃O₂ + H₂CO₃
(baking soda) + (vinegar) → sodium acetate + carbonic acid
Carbonic acid is unstable and undergoes a decomposition reaction to produce the carbon dioxide gas:
H₂CO₃ → H₂O + CO₂
resulting in NaHCO₃ + HC₂H₃O₂ → NaC₂H₃O₂ + H₂O + CO₂
The carbon dioxide escapes the solution as bubbles like the foamy lava experiment you did in 3rd grade. A dilute sodium acetate solution remains after the reaction. The sodium acetate (which is a salt) may offer a tiny bit of grease-removing ability, but it’s not much. Probably not enough to really notice.  So, really, all you’re doing, when you combine baking soda and vinegar to make a cleaning agent, is cleaning with very neutralized water with just a tiny amount of salt in it.
That’s not going to get your clothes very clean, and it’s certainly not going to soften your fabrics much.

More On Laundry Soap

In our last article we determined that OxiClean was redundant if we add Super Wash Soda and Borax together in hot water.  But it got me thinking, "What about the Super Wash Soda and the baking soda?".

Super Wash Soda + hot water = carbonic acid + sodium hydroxide (lye)
Na2CO3 + 2 H2O --> H2CO3 + 2 NaOH
carbonic acid is just carbon dioxide enriched water H2CO3 ↔CO2 + H2O 

baking soda + hot water = a couple different possibilities
NaHCO3 + H2O --> NA+ + HCO3- + H2O
NaHCO3 + H2O --> NA+ + H2CO3 + OH-

Once baking soda is dissolved, the dissolution products are the Na+ ion and the HCO3- ion . The HCO3- ion reacts with water to produce H2CO3 and a OH- ion. The H2CO3 will decompose into water and carbon dioxide.
Simple experiment: add a little baking soda to a dish and add hot water. Do you hear a fizz? That is carbon dioxide gas escaping!

As we all know, lye has a pH of about 13  to 14. Baking soda or sodium bicarbonate is a light alkaline with a pH of 8 to 9.  So, whether we use baking soda or Super Wash Soda we will get an alkaline bath that will help clean our clothes.  My conclusion is that baking soda is a poor replacement for Super Wash Soda, and is not necessary to add to the laundry detergent because I don't have hard water.

DIY Laundry Soap

1 box Super Wash Soda(Na2CO3) - pH 11
1 4 lb. box Baking Soda (NaHCO3) - pH 8.3
1 box Borax (Na2B4O7·10H2O) - pH 9.5
1 tub OxiClean (Na2CO. H2O2)
True Soap (Castile, Zote, FelzNaptha. Ivory, Yardly, Kirks, Etc.) Depending of the variety I use 2-4 bars.
Smell good boosters (this batch was made with Downy Unstopables sweet sizzle)

I was curious why home made detergent works so well, so i began to examine the chemical break down. After examining the results, I discovered I am wasting my money by adding OxiClean. SHOCK! So this is the break down:
One of the active ingredients in OxiClean is sodium percarbonate, an adduct of sodium carbonate (see super wash soda) and hydrogen peroxide (H2O2). Sodium percarbonate (OxiClean powder) must be added to water to be activated. When activated, it breaks down into hydrogen peroxide and sodium carbonate in solution. The bubbling action, or the release of oxygen molecules, loosens stain molecules from fibers so they can be rinsed away. Chemically, it is like a solid form of hydrogen peroxide which releases oxygen when water is added. Quite simply, the way it is made is by simply treating sodium corbonate with hydrogen peroxide!
Why is it a waste to add the OxiClean? The Borax, when dissolved in hot water, breaks down into hydrogen peroxide. Now add the super wash soda and you get OxiClean.
Why does the detergent work so well? Washing soda breaks some of the molecular bonds in water making water "wetter" and lowering the surface tension of the water so that the soap can be more effective. Borax has many chemical properties that contribute to its cleaning power. Borax and other borates clean and bleach by converting some water molecules to hydrogen peroxide. The pH of borax is about 9.5, so it produces a basic solution in water, thereby increasing the effectiveness of bleach and other cleaners. Borates bonds with other particles to keep ingredients dispersed evenly in a mixture, which maximizes the surface area of active particles to enhance cleaning power. Baking soda softens water by binding with Calcium and Magnesium forming solid, which can be rinsed off the fabric. Castile soap provides a clean, fluffy lather in both hard and soft water. Potassium hydroxide converts the oils into soap and glycerine, thus requiring less water for a lather than traditional liquid soap. When used for cleaning, soap allows insoluble particles to become soluble in water and then be rinsed away. The cleansing action of soap is determined by its polar and non-polar structures in conjunction with an application of solubility principles. The long hydrocarbon chain is non-polar and hydrophobic (repelled by water). The "salt" end of the soap molecule is ionic and hydrophilic (water soluble).  For example: oil/fat is insoluble in water, but when a couple of drops of dish soap are added to the mixture, the oil/fat apparently disappears. The insoluble oil/fat molecules become associated inside micelles, tiny spheres formed from soap molecules with polar hydrophilic (water-attracting) groups on the outside and encasing a lipophilic (fat-attracting) pocket, which shields the oil/fat molecules from the water making it soluble. Anything that is soluble will be washed away with the water.