Transcript Toxic Chemicals

Industrial Chemistry
Part ii
Dr. Ramy Y. Morjan
Faculty of Science
The Islamic University-Gaza
2011
Formulation Chemistry
Is the mixing of compounds/substances that DO NOT
react with each other but produce a mixture with the
desired characteristics/properties to suit a particular
application/use.
All product development starts from an idea or dream
that are converted into a physical form by combining
multiple ingredients.
Many modern products contain a combination
of several chemical substances, each contributing an
advantage to the finished product for a particular
application and use.
 A broad range of useful household products
are the result of the science of formulation
chemistry.
Cosmetics and other 'personal products‘
Perfumes, Hair colouring products, Deodorants
and antiperspirants, Detergents - liquids/gels
(e.g. washing up liquids/shampoos) and soaps
blocks/powders
Paints
Pharmaceutical products
Inks and Dyes
Adhesives
Characteristics of formulation chemistry
Since no reactions happen in making the mixture,
most formulations are prepared by measuring liquids
by volume and solids by mass ('weight').
In formulating chemistry products, the chemist
needs problem-free ingredients that have been tested
and found to be safe and effective.
Products are composed of multiple ingredients of
different physico-chemical properties.
In the process of formulation, all ingredients lose their
intrinsic identity.
Formulation is the accurate balance of all ingredients
in a single physical entity.
In order for all ingredients to take shape into specific
physical form, there plays an invisible physical
chemistry.
Cosmetics formulation is more than just simple
mixing of all ingredients. There must be chemistry
behind putting together all ingredients.
Without chemistry it would be called a “mixture” rather
than a formulation !!!
Formulation product is composed of two main parts
1) Structural Part
Chemical attraction between waxes and oils determines
the visco-elastic characteristics of product. If there is
a stable structure of the product, then that will be a
good start to combine the pigments uniformly for the
desired application properties.
The chemistry of individual ingredients determines the
texture of finished goods. It is the mystery of
chemistry how the same molecular weight can give
products completely different texture and properties.
Empirical formula: C18H36O2 (stearic acid): Waxy
Empirical formula: C18H36O2 (isostearic acid): Liquid
Surface Active Agents
Surfactants are "Surface Active Agents":
Surfactants are usually organic compounds that are
Amphiphilic
They contain both hydrophobic and hydrophilic groups
Surfactants are made up of two parts, a head and a
tail that exhibit differing properties.
Tail is hydrophobic (it tends to distance itself from H2O
The head is hydrophilic (it is attracted to water)
Surfactants are compounds that stabilize mixtures
of oil and water by reducing the surface tension
at the interface between the oil and water
molecules.
Surfactants are broadly classified into the
following four groups based on the ionic
charges they carry:
Anionic surfactants
Nonionic surfactants
Cationic surfactants
Amphoteric surfactants
The tail of surfactants can be:
1) A hydrocarbon chain:
Aromatic hydrocarbons , alkanes , alkenes, alkyne.
2) Alkyl ether chain (Alkoxylated surfactants)
i) Polyethylene oxides:
Inserted to increase the hydrophilic character of surfactant.
ii) Polypropylene oxides
Inserted to increase the lipophilic character of a surfactant.
Fluorinated Surfactants
Are synthetic organofluorine chemical compounds that
have multiple fluorine atoms
The Head of surfactants can be:
A surfactant can be classified by the presence of
formally charged groups in its head.
Anionic surfactants
These have a negatively charged end of the molecule.
Gives it the hydrophilic part of the molecule.
These negatively charged parts of the molecules are
usually
Sulfonates, Sulfates, or Carboxylates.
Neutralized by positively charged metal cations such
as Na or K
Carboxylates
Alkyl benzene Sulphonates
Uses of Ionic Surfactants
Cleansing Formulation
Shampoo & Hand wash
Bath gels & Tooth Paste
Soaps & Detergents
Nonionic surfactants
These are surfactants that have no ions. They derive their
polarity from having an oxygen rich portion of the molecule
at one end and a large organic molecule at the other end.
Partial net-negative charge which makes the whole molecule
polar and able to participate in hydrogen bonding with water
Examples of nonionic surfactants are alcohol
ethoxylates, nonylphenoxy polyethylenoxy alcohols,
and ethylene oxide/propylene oxide
Cationic surfactants
These are positively charged molecules usually
derived from nitrogen compounds.
They are not commonly used as cleaning agents in
hard-surface cleaners .
Many cationic surfactants have bacteriacidal properties
that are useful in creating disinfectants that leave a
cationic disinfectant film on the surface.
Cationic surfactants are usually incompatible with
anionic surfactants, because they will react with the
negatively charged anionic surfactant to
form an insoluble or ineffective compound.
Amphoteric surfactants
Those surfactants that change their charge with pH.
They can be anionic, nonionic, or cationic depending
on pH.
CH3
N+CH2COOCH3