Sodium Polyacrylate

Sodium Polyacrylate

Controversies

Conclusion

History

Properties

Reaction Mechanism

Introduction

• FDA Approval
• GRAS (Generally Recognized As Safe.

Dissolution of polyacrylate

Physical Properties

•Sodium polyacrylate is a polymer made of a long chain of acrylic acid.

• Sodium polyacrylate is synthesized mainly through the process of emulsion polymerization.

• Until the 1970s, cellulosic or fiber-based products were used for water absorption.

• In the early 1960s, the USDA conducted research to develop a super absorbent polymer.

• Robert Niles Bashaw, Bobby Leroy Atkins, and Billy Gene Harper are considered the first inventors of sodium polyacrylate.

• Synthesised for the Dow Chemical Company in 1966; oldest patent record.

Sodium polyacrylate in its gel form

Health

• Sodium polyacrylate in diapers is a contributing factor of staph infections.

• It is able to absorb all of the oils and moisture from the skin.

• This is expected considering that babies wear them constantly for years.

Sodium atoms are

linked to oxygen atoms

• Sodium polyacrylate is a polymer made up of one repeating formula, linked together in a long flexible chain.

• It is a substance commonly used in manufacturing industries and it is most notably known for being used in the making of diapers.

Emulsion

When dry: White powder

1966

When wet: Gel like substance

:The polymer is folded

in a dense coil

Gel state:

Powder state

Thickening agent

Na

Polymer

• An emulsion is mixture of two or more liquids that are normally immiscible

• One liquid is dispersed and held inside of another liquid by a substance called the emulsifier (surfactant).

Applications

Polymerization

The link breaks when

it dissolves in water

Sequestering agent

When it dissolves in water, sodium detaches from polymer and the chain becomes negatively charged and unfolded.

• Sodium polyacarylate is man-made substance first invented in 1966 but started to be used in industries in 1970s.

• It is a known as SAP (Super absorbent polymer) due to its special ability to absorb up to 800 times its mass in water.

• Polymer is synthesized from its monomer, acrylic acid, through the process of emulsion polymerization.

• It has a variety of industrial uses.

• Since it has been used for a short period of time, we should be cautious of its potential harm.

1. A surfactant is dissolved in water and forms micelles.

2. The monomer and the free radical initiator are added.

3. The initiator travels into the micelles and reacts with the monomer molecules

• It only began to be used commercially In the early 1970s when Victor Mills applied their usage in the creation of disposable diapers.

• BY 1957, Mills was 60 and had been working for P&G for 31 years

• P&G had recently acquired Charmin Paper Company

• Victor Mills is the man who gave the world Pampers.

- Absorbs as much as 300 times its mass in tap water and 800 times for distilled water.

• It is a synthetic substance.

• Its distinguished properties make it commercially valuable

• Concerns about its effects on human health and the environment.

Environment

• They account for an estimated 2% of the garbage generated in the U.S. Every baby uses 8-10 diapers per day.

• Also, if the chemical enters sewer or drainage systems it will swell up and cause serious clogging.

• Since it has only been used in the past couple decades, the full affect of sodium polyacrylate are have yet to be fully known.

+ O

1.5

2

propene + oxygen ----> acrylic acid + water

+ H O

2

acrylic acid

acrlyic acid monomer unit

Other Properties

• Nappy rash caused by wet skin was a real problem, and the task of washing cloth nappies was causing a considerable workload for hospital laundry services.

• Today Sodium Polyacryate is now used in many commercial products

- Density:1.22g/cm3

Chemical Formula: [-CH2-CH(COONa)-]n

polyacrylic acid + sodium hydroxide ---> sodium polyacrylate + water

- Non-toxic

Fuel Tanks

Coating

Astronaut suit

Agriculture

Applications

Special effect Toys

Fake snows