5.c.raw material testing.ppt

7/23/2019 5.c.Raw material testing.ppt

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COMPOUNDING

The mixture of rubber and ingredients used for

manufacture of any rubber product is called compound and

the art of maing such a compound is called compounding!

Ingredients for product manufacture

"! Polymer or rubber

#! Crosslining agents$! %ccelerators for crosslining reaction

&! %ccelerator modifiers '%cti(ator and retarders)

*! %ids to processing

+! ,einforcing fillers '-lac. mineral and organic)

/! %ntidegradants

0! %ids to (olume cost 'inert fillers)

1! Colouring materials

"2! 3pecific additi(es



Different stages of 4uality control

"! ,a5 material testing

#! In process testing

$! Product testing



Important polymers

Natural rubber 'N,)

3tyrene butadiene rubbers '3-,) Polyisoprene rubbers 'I,)

Isobutene isoprene '-utyl) rubbers 'II,)

Chloroprene 'Neoprene) rubbers 'C,)

%crylonitrile butadiene 'Nitrile) rubbers 'N-,)

6thylene propylene rubbers '6PM and 6PDM)

Chlorosulphonated polyethylene rubbers 'C3P6)

'7ypalon) 3ilicone rubbers '8)

Polysulphide rubbers 'Thiools)

Polyurethane rubbers



Polymer 6lements present %ppearance

N, C.7 Translucent. stra5 colour

3-, C.7 Opa4ue. 5hite-, C.7 Translucent

C, C.7.Cl Opa4ue. 5hite

N-, C.7.N Opa4ue. cream colour

II, C.7 Translucent. cream colour

C3M C.7.Cl.3.O Opa4ue. 5hite

T, C.7.3 Opa4ue. cream

8 C.7.3i.O Translucent. soft

6PDM C.7 Translucent

PU C.7.N.O Can be transparent or

5ide range of colour



Polymer identification

"! -urning test

#! 6lemental analysis$! 3olubility test

&! Colour reactions

*! Instrumental analysis

-urning test

Polymers

Materials burn and continues to

burn on remo(al from the flame

eg! N,. 3-,. I,.-,. etc!

Materials burn but

extinguishes itself on

remo(al from the flame

eg! C,. C3P6



Polymer 9lame colour Odour

N, and I, :ello5. smoy Pungent

3-, :ello5. (ery smoy 3tyrene

N-, :ello5. smoy 35eet

-, :ello5 5ith blue base.

smoy

35eet

6PDM ; 6PM :ello5 5ith blue base ,esembles burning

candle 5ax

II, :ello5.smoy <ight s5eet



6lemental analysis '<assaigne=s test)

3odium fusion extract

Nitrogen

Nitrile rubber.

Polyurethane

Chlorine

Neoprene.

7ypalon

3ulphur

Thiool.

7ypalon



7eat the polymer 5ith con! Nitric acid

Disintegration

N,. I,. 3-,. -,

No disintegration

II,. 8. 6PDM



>et Tests?

9or 5et test. ra5 rubber is pyrolised and out coming (apour is

tested by solution "!

Preparation of solution "?

"g of p@dimethyl aminobenAaldehyde and 2!2" g of hydro4uinone

are dissol(ed in "22 cc of absolute methanol! To this * cc of 7C<

and "2 cc of ethylene glycol is added!

Procedure?

,ubber is cut into small pieces and is placed in the test tube

containing side arm! The test tube is cored and heated 5ith

micro burner until it is decomposed and (apour appears at themouth of side arm! Bapour is introduced into the test tube

containing solution ". and the change of colour is noted!

Next this solution is transferred into bigger test tube and to it *

cc of methanol is added and heated on 5ater bath! %fter * min!

heating. colour change is noted!



6xperiment Initial colour Colour after heating5ith methanol Inference

Pyrolised

(apour is

passed

through the

solution

Pale yello5 Pale yello5 -lan

Pale yello5 Pale blue or bluish C,

Pin to red -lue N-,

Pale blue Green 3-,

Pinish (iolet Biolet blue N, or I,

Pale blue Pale blue II,

Pyrolysis Test 5ith solution "



6xtraction sol(ent for (ulcaniAed ,ubber

6lastomer ,a5 (ulcaniAed

N, %cetone. Methanol.#@propanol 'iso@propyl alcohol)

%cetone. Methanol.M6 'Methyl ethyletone)

-,. 3-,.I, %cetone. #@propanol %cetone. M6

II, %cetone. M6 %cetone. M6

C, <ight petroleum'+2 @ 02C)

#@propanol. Methanol

<ight petroleum'+2 @ 02C).

#@propanol. Methanol

N-, <ight petroleum'+2 @ 02C)

<ight petroleum'+2 @ 02C)



I, 3pectrum

The absorption peas

Isoprene ,ubber 3-, ,ubber

>a(e number cm@" Intensity >a(e number cm@" Intensity

022 m +11 (s

0$+ (s /*0 s

00* s 121 m

121 s 1+# s

"$/2 s 112 m"+&2 m "&12 M



I, 3pectrum

The absorption peas

N-, ,ubber C,


121 m 0#2 s

1+# s """2 s

"$22 m "$"* m

###2 (s "++* (s



I, 3pectrum

The absorption peas

-utyl ,ubber Polybutadiene ,ubber


00* 3 /&" (s

"##2 m 0"$ 5

"#*2 m 121 s

"$/2 s 1+# s

"$12 s 112 m



6PDM ,ubber ChlorosulphonatedPolyethylene ,ubber

'C3P6)


/"2 m /$2 m

/+2 m 0"$ 5

121 3 121 s

"20$ 3 112 m

""&* m ""*2 s

"$/2 s "#+* m

"$/2 (s



8uantitati(e analysis

9or N, –

estimate the hydrocarbon content 9or each & isoprene units in the rubber hydrocarbon

$ moles of acetic acid are produced!

9or Neoprene rubber – estimate the chlorine content

Neoprene content E #!&1 x percentage chlorine content

9or Nitrile rubber – estimate the nitrogen content

Nitrile rubber content E $!1 x percentage nitrogen content



CharacteriAation of carbon blac

Particle siAe - Microscope or electron microscope

3tructure - D-P absorptometer 'dibutyl phthalate

absorptomer)

p7 - p7 meter

D-P absorption No! is the amount of D-P absorbed by

"22 g of blac to attain the specified tor4ue



Mineral fillers

• Moisture content

• Particle siAe

• 3pecific gra(ity



Petroleum oils %romatic. Naphthenic . Paraffinic

Paraffinic oils Good colour. good stability. good

sol(ent po5er for saturated

compounds and higher cost

%romatic oils Poor colour. poor stability. good

sol(ent po5er for polar compounds

and lo5er cost

Naphthenic oils 9all in the middle bet5een these t5o

CharacteriAation of oils



Oil type %sphaltenes.

F max

Polar compounds.

F max

3aturates.

F

%romatic

"2"

"2#

2!/*

2!*2

#*

"#

#2 'max)

#2 $*

Naphthenic

"2$ 2!$ + $* +*

Paraffinic

"2& 2!" " +* 'min)

Classification of Oils '%3TM D###+)



Oils are checed for

3pecific gra(ity

9lash point

%niline point



3pecific gra(ity?

>eight of a gi(en (olume of oil to the 5eight of an e4ual

(olume of 5ater

9lash point?Temperature of the oil 5hen a flame 5ill ignite (apours

%niline point?

The temperature at 5hich e4ual portions of an oil and

aniline are miscible

%niline point decreases 5ith increasing aromatic content!<o5 aniline point oils tend to be compatible 5ith most

rubbers



Oil Type 3pecificgra(ity

9lash point. C %niline pointrange. C

%romatic "!222 ##2 #/ @ *&

Naphthenic 2!1$& #$# ** @ 1#

Paraffinic 2!0/+ $2# 1$ @ "#*



Polymer Compatible

N, . -, . II, Naphthenic

3-, %romatic

N-, 7ighly polar esters

'DOP . D-P)

6PDM Paraffinic .Naphthenic

C, %romatic

C3M %romatic



%ccelerators

Name Melting point.

C

3pecific gra(ity

Diphenyl guanidine'DPG)

"&* H # "!"0 H 2!2#

Mercapto benAothiaAole

'M-T)

"/* H # "!&1 H 2!2#

DibenAothiaAyldisulphide 'M-T3)

"+0 H # "!*$ H 2!2#

Tetra ethyl thiuramdisulphide 'T6TD)

/2 'approx!) "!$

inc diethyl dithio@carbamate 'DC)

"/0 'approx!) "!&0 H 2!2"



%ntioxidants

Name Melting point.C

3pecificgra(ity

Phenyl@-@naphthylamine'P-N)

"2* 'approx) "!#"

Diphenyl@p@ phenylenediammine 'DPPD)

"$# H # "!#& H 2!2#



Chemical -urning test 3olubility

3ulphur -urns 5ith a blue flame.

pungent smell. lea(esno residue

Completely soluble in

carbon disulphide

inc oxide -ecomes yello5 5hilehot and 5hite 5hile cold

Completely soluble inhydrochloric acid orsulphuric acid 5ithout

gi(ing anyeffer(escence! 3houlddissol(e completely indil! acetic acid!



Chemical 3odium

carbonate test

3olubility Melting

point3tearic

acid

%dd fe5 crystals

of stearic acid to a

hot saturated

solution of sodium

bicarbonte!

6ffer(escence

around the crystal

indicates stearic

acid!

>arm about " g of

the sample in about

"2 ml of methanolic

potassium

hydroxide! 3tearic

acid should dissol(e

completely

/2

C



Chemical p7 3olubility

3ilica orsilicate

Neutral 'bet5een +and 0)

3hould not be solublein con! 7Cl of 7#3O&

and should not gi(e

effer(escence

Clay Neutral >ith dil! 7C<. it shouldnot gi(e effer(escence

-arium

sulphate

Neutral >ith dil! 7Cl. it should

not gi(e effer(escence

9illers



Chemical 3olubility Test for calcium

>hiting

'Calciumcarbonate)

>ith dil! 7Cl. it

should gi(eeffer(escence andshould be completelysoluble!

7Cl soluble part is

treated 5ith ammoniumhydroxide andammonium oxalate!>hite precipitate isformed!

Chemical 3olubility Test for Magnesium

Magnesiumcarbonate

>ith dil! 7Cl. itshould gi(eeffer(escence and

should be completelysoluble!

7Cl soluble part istreated 5ith ammoniumhydroxide and

diammonium hydrogenphosphate! >hiteprecipitate is formed!

5.c.raw material testing.ppt

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