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TERM PAPER

OF

CHE-101

TOPIC:- EXPLAIN SURFACTANTS.

SUBMITTED BY

SUBMITTED TO

NAME- BITTU KUMAR LECT. JYOTI

MAM

SECTION-E2801 (DEPARTMENT

OF CHEMISTRY.)

ROLL NO. A05

REGISTRATION NO. -10808479

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ACKNOWLEDGEMENT

As usual a large number of people deserve my thanks for

the help they provided me for the preparation of this

term paper.

First of all I would like to thank my teacher Lect. Jyoti

mam for her support during the preparation of this topic. I

am very thankful for her guidance.

I would also like to thank my friends for the

encouragement and information about the topic they

provided to me during my efforts to prepare this topic.

At last but not the least I would like to thank seniors for

providing me their experience and being with me during

my work.

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-:TABLE OF CONTENTS:-

1.1 INTRODUTION

1.2 PROPERTIES

1.3 TYPE OF SURFCATANTS

1.3.1ANIONIC SURFACTANTS

1.3.2CATIONIC SURFCTANTS

1.3.3NONIONIC SURFACTANTS

1.3.4AMPHOTERIC SURFACTANTS

1.4 APPLICATION OF THE SURFACTANTS

1.5 HARMFULL EFFECT OF SURFACTANTS

1.6 REFERENCES

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1.1 INTRODUCTION:-

The term surfactant (short for surface-active-agent) designates a substance whichexhibits some superficial Surfactants provide remarkable benefits in many textile

wet processes. A surface active chemical is one which tends to accumulate at a

surface or interface. An interface is the area of contact between two substances.

The surface tension of a liquid is an internal pressure caused by the attraction of

molecules below the surface for those at the surface of a liquid. This molecular

attraction creates an inward pull, or internal pressure, which tends to restrict the

tendency of the liquid to flow and form a large interface with another substance.

The surface tension (or inter-facial tension if the interface is not a surface)

determines the tendency for surfaces to establish contact with one another.

Therefore, surface tension is responsible for the shape of a droplet of liquid. If the

surface tension is high, the molecules in the liquid are greatly attracted to one

another and not so much to the surrounding air.

If the droplet of water is in contact with a solid such as a fabric, its shape will also

be affected by the surface tension at the solid/liquid interface. If the surface tension

in the liquid is lower, the droplet forms a more ellipsoidal shape.

The following are the surface tensions for some liquid substances:-

SUBSTANCE SURFACE TENSION

1. water 73 dynes/cm

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2. mercury 480 dynes/cm

3. benzene 28 dynes/cm

4. ethanol 22 dynes/cm

Because of its lower surface tension, ethanol will flow and form a larger area of

contact (surface) with a solid than with water. Mercury, with its very high surface

tension, does not flow but breaks into droplets if given the opportunity. Surface

active agents interfere with the ability of the molecules of a substance to interact

with one another and, thereby, lower the surface tension of the substance.

Surfactants used in industrial applications usually cause a dramatic decrease in

surface tension when used at low concentration.

1.2 PROPERTIES:-

Chemically, surfactants are amphipathic molecules. That is, they have two

distinctly different characteristics.

1. Polar

2. Non polar

In different parts of the same molecule.

Therefore, a surfactant molecule has both hydrophilic (water-loving) and

hydrophobic (water-hating) characteristics. Symbolically, a surfactant molecule

can be represented as having a polar head and a non polar "tail" as shown below.

non polar polarhead(+)

trailor

1.2.1 CHARACTERSTICS OF TAIL GROUP(HYDROCARBON

AND FLUROCARBON - APOLAR):-

a). Weak affinity for bulk solvent

b). Strong affinity for air and oil

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c). Adsorption at air (oil)-water interface.

1.2.2 CHARACTERSTICS OF HEAD GROUP:-

a). Strong affinity for bulk solvent (water)

b). Weak affinity for air and oil

c). Charged (polar) or neutral

d). Adsorption at mineral-water interface.

Examples: sulphate, (SO3) amines.

Example of polar and non-polar molecule:

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The hydrophobic group in a surfactant for use in aqueous medium is usually a

hydrocarbon chain but may be a fluorocarbon or siloxane chain of appropriate

length. The hydrophilic group is polar and may be either ionic or nonionic.

Since surfactant molecules have both hydrophilic and hydrophobic parts, the most

attractive place for them in water is at the surface where the forces of both

attraction and repulsion to water can be satisfied. One other way that surfactants

interact to satisfy natural forces of attraction and repulsion between molecules is

by formation of micelles. Surfactant molecules aggregate in water forming

micelles (see Figure). Micelles consist of hydrophobic interior regions, where

hydrophobic tails interact with one another. These hydrophobic regions are

surrounded by the hydrophilic regions where the heads of the surfactant molecules

interact with water.

Schematic representation of

surfactant molecules at surface and

surfactant micelle

At very low concentration in water, surfactant molecules are unassociated. At

higher concentration of surfactant in water, micelles form, The concentration at

which micelles form is called the critical micelle concentration (CMC). The

surface tension of water undergoes a precipitous decrease, and the detergency ofthe mixture increases dramatically at the CMC.

1.3 TYPES OF SURFACTANTS:-

Surfactants fall in the following

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Classification according to the nature of the hydrophilic group:-

1. Cationic: hydrophilic head is positively charged;

2. Non-ionic: hydrophilic head is polar but not fully charged; and3. Anionic:- hydrophilic head is negatively charged;

4. Amphoteric: molecule has both potential positive and negative groups;charge depends on pH of the medium.

1.3.1 ANIONIC SURFACTANTS:-

In solution, the head is negatively charged. This is the most widely used type ofsurfactant for laundering, dishwashing liquids and shampoos because of its

excellent cleaning properties and high sudsing potential. The surfactant is

particularly good at keeping the dirt away from fabrics, and removing residues

of fabric softener from fabrics

Anionic surfactants are particularly effective at oily soil cleaning and oil/clay

soil suspension. Still, they can react in the wash water with the positively

charged water hardness ions (calcium and magnesium), which can lead to

partial deactivation. The more calcium and magnesium molecules in the water,

the more the anionic surfactant system suffers from deactivation. To prevent

this, the anionic surfactants need help from other ingredients such as builders(Ca/Mg sequestrants) and more detergent should be dosed in hard water.

The most commonly used anionic surfactants are alkyl sulphates, alkyl

ethoxylate sulphates and soaps.

A). SULPHATES:-

The sulfonate group is an effective solubilizing group when attached to an

alkyl, aryl, or alkylaryl hydrophobe. Since the sulfonate group is a strong acid,the sulfonate surfactants are soluble and effective in acidic as well as in alkaline

medium.

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Example: Sodium Dodecyl Sulphate C12H25O(SO3)Na

B). SULPHONATES:-

Various fatty alcohols can be reacted with chlorosulfonic acid or sulfur trioxide to

produce their sulfuric acid esters. The properties of these surfactants depend on

the alcohol chain length as

Example: Sodium dodecylbenzene sulphate

C). FATTY ACID AND SOAPS:-

Example: Sodium oleate. CH3(CH2)7=CH(CH2)7COONa

D). XANTHATHES:-

Example: Sodium ethyl xanthate

CH3CH2OCS2Na

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E). DITHIOPHOSPHATE:-

1.3.2 CATIONIC SURFACTANTS:-

Cationic surfactants account for only 5-6% of the total surfactant production.

However, they are extremely usefull for some specific uses, because of their

peculiar properties. They are not good detergents nor foaming agents, and they

cannot be mixed in formulations which contain anionic surfactants, with the

exception of non quaternary nitrogenated compounds

They exhibit two very important features.:-

1. Their positive charge allows them to adsorb on negatively charged substrates,

as most solid surfaces are at neutral pH. This capacity confer to them an

antistatic bahavior and a softening action for fabric and hair rinsing. The

positive charge enable them to operate as floatation collectors, hydrophobating

agents, corrosion inhibitors as well as solid particle dispersant. They are usedas emulsifiers in asphaltic emulsions and coatings in general, in inks, wood

pulp dispersions, magnetic slurry etc.

2. Many cationic surfactants are bactericides. They are used to clean and aseptize

surgery hardware, to formulate heavy duty desinfectants for domestic and

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hospital use, and to sterilize food bottle or containers, particularly in the dairy

and beverage industries.

TWO COMMON TYPE OF CATIONIC SURFACTANTS:-

1. LONG CHAIN AMMINE:-

The long chain amine types are made from natural fats and oils or from synthetic

amines. They are soluble in strongly acidic medium but become uncharged and

insoluble in water at pH greater than 7. For example:-

Benzalkonium or alkyl dimethyl benzyl-ammonium chloride

2. QUARTENARY AMMINE SALT:-

Quaternary amine type cationic surfactants are very important as fabric softeners.

They absorb on the surface of fibers with their hydrophobic group oriented away

from the fibers. This reduces the friction between fibers and imparts a soft, fluffy

feel to the fabric.

1.3.3 NONIONIC SURFACTANTS:-

Nonionic surfactants do not produce ions in aqueous solution. As a consequence,

they are compatible with other types and are excellent candidates to enter complex

mixtures, as found many commercial products. They are much less sensitive to

electrolytes, particularly divalent cations, than ionic surfactants, and can be used

with high salinity or hard water. Nonionic surfactants are good detergents, wetting

agents and emulsifiers. Some of them have good foaming properties. Some

categories exhibit a very low toxicity level and are used in pharmaceuticals,cosmetics and food products.

Nonionic surfactants are compatible with other types of surfactants. Their low

foaming tendency can be an advantage or disadvantage depending on

requirements. They are good dispersing agents in many cases. They are more

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effective than sulfonate surfactants in removing s oil from hydrophobic fibers but

are inferior to anionic surfactants for soil removal from cotton.

Main Nonionic Surfactants

Surfactant Type % Total

Ethoxylated Linear Alcohols 40Ethoxylated Alkyl Phenols 15

Fatty Acid Esters 20

Amine and Amide Derivatives 10

Alkylpolyglucosides ---

Ethleneoxide/Propyleneoxide Copolymers ---

Polyalcolols and ethoxylated polyalcohols ---

Thiols (mercaptans) and derivates ---

THREE TYPE OF CATIONIC SURFACTANTS:-

1. ETHOXYLATED ALCOHOLS AND ALKYLPHENOLS:-

2. FATTY ACID ESTER:-

The esterification of a fatty acid by a -OH group from polyethyleneoxide chain

tip or polyalcohols generates an important family of nonionic surfactants.Their

compatibility with biological tissues which make them suitable for

pharmaceuticals, cosmetics and food stuffs.

3. NITROGENATED NONIONIC SURFACTANTS:-

It has been said previously that amines and amides can be ethoxylated. The first

EO group must be added at acid pH, whereas the other ones (from the second

group on) are added at alkaline pH.

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Products such as ethoxylated amines consists in a fatty amine with one or

two polyethylene glycol chains. Those with only 2-4 EO groups behave as

cationic surfactants at acid pH. They are used as corrosion inhibitors and

emulsifiers with a better water solubility than most cationics. Imidazoles,

i.e. cyclic alkyl-diamines, are ethoxylated to produce fabric

softeners for machine-washing, which also provide an anticorrosion

protection for the hardware.

1.3.4. AMPHOTERIC SURFACTANTS:-

Amphoteric or zwitterionic surfactants have two functional group, one anionic and

one cationic. In most cases it is the pH which determines which of the groups

would dominate, by favoring one or the other ionization: anionic at alkaline pH

and cationic at acid pH. Near the socalled isoelectric point, these surfactants

display both charges and are truly amphoteric, often with a minimum of interfacial

activity and a concomitant maximum of water solubility. Amphoteric surfactants,

particularly the aminoacid ones are quite biocompatible, and are used inpharmaceuticals and cosmetics.

1. IMIDO PROPIONIC ACIDS:-

Their general formula is HOOC-CH2-CH2-RN+H-CH2-CH2-COO-. Their

isoelectric point is around pH = 2-3. They are thus more water soluble than the

previous ones. They are used as textile softeners. Dicarboxylic compounds of alkyl

imidazole, in which the alkyl group is located on the carbon placed between the

nitrogen atoms, are used in cosmetics and de luxe soap bars.

2. QUATERNIZED COMPOUNDS:-

Quaternized compound have similar structures. The most important are betaines

and sulfobetaines or taurines, which have a single methylene group between the

acid and the quaternary ammomium.

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R-N+(CH3)2-CH-COO- alkyl betaine

R-N+(CH3)2-CH2-SO3- alkyl sulfobetaine

These surfactants are amphoteric at neutral and alcaline pH, and cationic at acid

pH (at which the carboxylic acid is not ionized). Since the nitrogen atom is

quaternized, these surfactants always display a positive charge. They tolerate a

high salinity, particularly divalent cations, e.g. calcium and magnesium. They are

the most used class of amphoteric surfactants. They are found in softeners for

textiles, hair rinse formulas, and corrosion inhibition additives. They are good

foam boosters because of their cationic characteristics.

1.4 APPLICATION OF SURFACTANTS:-

1. It is act as anti-foaming agent

2. It useful in making inks

3. Surfactants are added to gasoline as detergents, dispersants, corrosion inhibitors

and carburetor anti-icing additives.

4. Detergents, dispersants and corrosion inhibitors, similar to those used in

gasoline, are being used in some diesel fuels. Deposit problems which occur in

the carburetor in gasoline engines.

5. It is used in paints, detemper.

1.5 HARMFUL EFFECT BY

SURFACTANTS:-

Some surfactants are known to be toxic to animals, ecosystems and humans, and

can increase the diffusion of other environmental contaminant. Despite this, they

are routinely deposited in numerous ways on land and into water systems, whetheras part of an intended process or as industrial and household waste. Some

surfactants have proposed or voluntary restrictions on their use. For example,

PFOS is apersistent organic pollutant as judged by the Stockholm Convention.

1.6REFERENCES:-

http://en.wikipedia.org/wiki/PFOShttp://en.wikipedia.org/wiki/Persistent_organic_pollutanthttp://en.wikipedia.org/wiki/Stockholm_Conventionhttp://en.wikipedia.org/wiki/PFOShttp://en.wikipedia.org/wiki/Persistent_organic_pollutanthttp://en.wikipedia.org/wiki/Stockholm_Convention

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BOOK

1. INDUSTRIAL SURFACTANTS- 2ND EDDITION- Ernest W. Flick

2. N.C.E.R.T CHEMISTRY

WEBSITE:-

1. http://docs.google.com/viewer?

a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFAC

TANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3j

RhFVP8B87PBHCmmk_Rbti1Np8RCH-

biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsU

w4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaA

2. http://en.wikipedia.org/wiki/Surfactant

http://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaAhttp://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaAhttp://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaAhttp://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaAhttp://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaAhttp://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaAhttp://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaAhttp://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaAhttp://docs.google.com/viewer?a=v&q=cache:GRuHsFbjeDMJ:www.p2pays.org/ref/03/02960.pdf+PDF+ON+SURFACTANTS&hl=en&gl=us&pid=bl&srcid=ADGEEShZ92xRqa2WCuoKYRBNuptdnyGP3jRhFVP8B87PBHCmmk_Rbti1Np8RCH-biFcwfw7g8hCVum3CmyUTDaOquhyI0Z8BQ4Hnz7C5eqgICWjNOOmO9H0hMCFsUw4h8CrEOmJLConV&sig=AHIEtbQq55O8F52ihJclEyhJG91bQvmLaA