Bettye Greene was born on March 20, 1935 in Fort Worth, Texas She attended segregated public schools and graduated from I.M. Terrell High School around 1952.and earned her B.S. from the Tuskegee Institute in 1955 and her Ph.D. from Wayne State University in 1962, studying under Wilfred Heller.
She entered Tuskegee Institute in Alabama, graduating with a B.S. in chemistry in 1955. Following her marriage to Veteran Air force Captain William Miller Greene in 1955, she attended Wayne State University in Detroit, where she earned her Ph.D. in physical chemistry working with Wilfred Heller(1962). Together Willetta Greene Johnson, Victor M. Greene, and Lisa Kianne Greene were born unto their union. She also taught undergraduate chemistry at this time. Her doctoral dissertation, "Determination of particle size distributions in emulsions by light scattering" was published in 1965.
She was elected to Sigma Xi, the Scientific Research Society.
Dow Chemical
In 1965, Greene joined the Dow Chemical Company's E. C. Britton Research Laboratory in Midland, Michigan. She was the first African-American woman to join the company in a professional position. Dr. Greene served as a Consultant on Polymers issues in the Saran Research Laboratory and the Styrene Butadiene (SB) Latex group often utilized her expertise and knowledge. At Dow, she researched colloid and latex chemistry, including interactions between latex and paper.
In 1970, Dr. Greene was promoted to senior research chemist at Dow Chemical. In 1973, she joined Dow Chemical's Designed Polymers Research Division, again working with latex, to find polymers that could improve latex. She was subsequently promoted to the position of senior research specialist in 1975. She continued to work for Dow Chemical until her retirement in 1990. She published several papers studying different properties that lend to the redispersement of latex. She also published work studying methodologies for determining the surface tension of liquids or solutions. She left Dow Chemical in 1990.
Dr. Greene filed for several patents during her career at Dow Chemical. In 1985, she was issued a patent entitled "Stable latexes containing phosphorus surface groups" describing a method of preparing a paper coating composition comprising the addition of from about 2 to about 30 percent of a modified latex containing phosphorus surface groups. In 1986, she was issued a follow-up patent entitled "Composite sheet prepared with stable latexes containing phosphorus surface groups" also employing emulsion polymerization techniques for preparing modified latex. In 1990, Dr. Greene was issued a patent entitled "Latex based adhesive prepared by emulsion polymerization" for the invention of a latex based pressure sensitive adhesive for coating conventional substrates to form an adhesive tape.
After decades of contribution to the science of polymers, she passed away in Midland on June 16 1995.
In addition to her work at Dow, Bettye Greene was active in community service in Midland and was a charter member of the Midland, Michigan Alumnae Chapter of the Delta Sigma Theta Sorority, Inc., a national service group for African-American women. Greene retired from Dow in 1990 and passed away in Midland on June 16, 1995.
Patents
Greene held a number of patents including a latex-based adhesive using a carboxylic acid copolymerizing agent, and latex polymers with phosphates used as coatings:
- 4968740: Latex-based adhesive prepared by emulsion polymerization
- 4609434: Composite sheet prepared with stable latexes containing phosphorus surface groups
- 4506057: Stable latexes containing phosphorus surface groups
Abstract
There are many different kinds of slime out there. Some slime is runny and liquid-like; other slime is thick and rubbery. Some slime glows in the dark, some is fluffy, and some is even magnetic! What set of properties makes the best slime? What kind of slime would you choose to make if you were selling slime as a toy in your own "slime shop"? In this project, you will experiment with different slime recipes and try to perfect one to make the best slime.Objective
Define desired properties for your slime, and then find the recipe that gives the best results.
Introduction
If you have ever played with slime, you know that it can be fun with all of its stretchy, bouncy, ickiness. Maybe you have noticed that some types of slime feel different than others. Have you ever wondered why slime behaves the way it does? It all has to do with chemistry. Chemistry is the study of matter, which is the stuff that everything around you is made of. Chemists are interested in finding out what different materials, such as slime, are made of, how these materials behave, and how they can be changed into other materials.
What is slime actually made of? If you have made slime before, you probably followed a recipe to put different ingredients together, similar to baking a cake. The ingredients used for slime usually include Elmer's® glue and borax. Elmer's glue is made up of a polymer. Polymers are long chain-shaped molecules.
The polymer chains in the Elmer's glue are long and very straight. The polymer chains can slide across each other easily, making the glue runny and "liquidy" (think of dumping a bunch of fresh-cooked spaghetti out of a pot). This changes, however, when you mix the glue with borax. The borax helps make connections between each of the polymer chains, as shown in Figure 1. This process is called crosslinking. This makes it harder for the polymer chains to slide around, making the glue thicker and turning it into "slime." In this project, you will use contact lens solution to make slime. It contains other ingredients (boric acid and sodium borate) that react with baking soda (another ingredient in your slime) to make borax.
Figure 1. Straight polymer chains (left) are linked together by borax to form a cross-linked polymer (right).
You might wonder if changing the recipe changes the properties of the slime. In science, a property is something about a material that you can observe and measure, for example, its weight, color, or stickiness. There are many different types of slime with different properties. Some slime is thin and runny; some slime is thick and rubbery. You can add extra ingredients to slime to make it sparkly, magnetic, or glow-in-the-dark.
Terms and Concepts
- Chemistry
- Matter
- Polymer
- Crosslinking
- Properties
Questions
- If you could make any slime you wanted, what properties would you want it to have?
- What ingredients do you think you would need to give your slime those properties?
- Search online for slime recipes. What types of slime do you find recipes for?
Materials and Equipment
This is an engineering design project, the exact list of materials you need may vary slightly. To make a typical basic slime recipe, you will need:
- Washable PVA school glue (like Elmer's®)
- Water
- Baking soda
- Contact lens solution (must contain both boric acid and sodium borate in ingredients)
- Food coloring
- Measuring spoons
- Measuring cup
- Mixing bowl
- Spatula
- Resealable plastic bags or food storage containers
You can also try various additives to change the properties of your slime:
- Glitter (sparkly slime)
- Iron filings (magnetic slime)
- Glow-in-the-dark paint (glow-in-the-dark slime)
- Thermochromic pigment (color-changing slime)
- Tonic water (glow-in-black-light slime)
- Foam shaving cream (fluffy slime)
Bibliography
- Dow Chemical Company. “Dr. Bettye Washington Greene (1935-1995),” n.d. Dow Chemical Company Historical Image Collection, Box 7, Folder Personnel--Greene, Betty. Science History Institute. Philadelphia. https://digital.sciencehistory.org/works/t722h939f.
- Rader, Andrew. (2005). Matter is the Stuff Around You. Rader's Chem4Kids. Retrieved December 13, 2005.
- Science Buddies Staff (n.d.). The Engineering Design Process. Science Buddies. Retrieved July 17, 2019.
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