Name :- Vatsal K. KapadiaBranch :- Plastic EngineeringRoll No. :- 1150011Internship at :- Larsen & Toubro Department :- Polymer Testing ( SDDC )

What is the material of this component ?

What is the material used by the competition ?

Is the vendor using the appropriate material ?

Which material can replace the current material for the betterment of the product ?

What is the composition in the material ? Is this a new material ?

Plastic Identification In General

Plastic Material

Press a hot rod (500 F) against the sample

Thermoplastics

Thermosets

(If softens)

Drop a small sample in water

Burn a small corner of the sample

Floats Sinks

Self

-

Extin

guish

ing

Continues to

burn

Materials:-1. Melamine Formaldehyde2. PhenolFormaldehyde3. UreaFormaldehyde

Materials:-1. Polyester2. Silicon3. Epoxy

Materials:- Polyethylene and Polypropylene

All other materials

Burn a small corner of the sample

No Flames Continues to Burn

Self Extinguishing

Materials :- PTFE, PVF, CTFE, FEP

Materials:- Drips- Acetal, ABS, Acrylics, Cellulose Acetate, PS etc. No Dripping:- Cellulose Nitrate, Polyurethane

Materials:- Drips-Nylon, Polysulfone, Polycarbonate No Dripping- PPS ,PVC

Elastomers

Drop a small sample in water

Materials:- TPV, TPO

Float

s

Sinks

Burn a small corner of the sample

Self

- Ext

ingu

ishi

ngMaterial:- Silicon

Materials:-Urethane,Polyester etc

Density of the Polymer(The Archimedean Principle)

Density of a substance is mass per unit volume. The symbol ρ (rho) is used to determine density

Unit:- g/cc

Significance of Density• The specific gravity or density of a solid is a property

that can be measured conveniently to identify a material

• To allow physical change in a sample• To indicate degree of uniformity among different

sampling units• Change in density of a single specimen may be due to

hangs in Crystallinity, loss of plasticizer absorption of solvent, or to other causes addition of Glass Fibers and Flame Retardents.

• Portions of a sample may differ in density because of difference in Crystallinity, thermal history, porosity, and composition (types or proportions of resin, plasticizer, pigment or filler).

MATERIAL DENSITY (g/cm3)ABS 1.06

ACETAL 1.43PMMA 1.19

NYLON 6 30% GF 1.35NYLON UNFILLED 1.12POLYCARBONATE 1.2

POLYSTYRENE 1.07PVC (Flexible) 1.25

PTFE 2.0HDPE 0.96LDPE 0.94

PP 0.92SMC 25% GF 1.753DMC 15% GF 1.814

Density of some Useful Polymers

Thermal Analysis

Thermal analysis is a branch of materials science where the properties of materials are studied as they change with temperature. Several methods are commonly used – these are distinguished from one another by the property which is measured

Thermal Analysis Techniques

DIFFERENTIAL SCANNING CALORIEMETRY

Differential scanning calorimetry or DSC is a thermoanalytical technique in which the difference in the amount of heat required to increase the temperature of a sample and reference is measured as a function of temperature.

DSC can tell you :-• Qualitative analysis• Sample purity• Melting points• Heat capacity• Glass transition

temperature (Tg)• Crystallization

temperature ( Tc)• Melting temperature• Percentage cure

DSC Graph Interpretation

A is seen in Amorphous ThermoplasticsB-C-D is seen in ThermosetsE-F-G is seen in Thermoplastic 

Materials Onset Temp. Melting point End point Meltng Energy

Unfilled Nylon 66 non FR

242 ˚C 266˚C 287˚C 80.09 J/g

30% GF FR nylon 6

189˚C 225˚C 249˚C 56J/g

30% GF FR nylon 66

227˚C 260˚C 277˚C 39.15J/g

30% GF FR PBT 208˚C 224˚C 252˚C 33.95J/g

DSC results of some materials:-

THERMOGRAVIMETRIC ANALYSIS 

Thermogravimetric Analysis (TGA) measures the amount and rate of change in the weight of a material as a function of temperature or time in a controlled atmosphere.

TGA will tell you:-

• Physical changes in materials.

• Compositional analysis of multi-component materials or blends

• Filler content of materials

• Glass % in the material• Moisture and volatiles

content

DSC Graph Interpretation

Plateau: It is the segment AB of the curve where the weight of the sample remains unchanged. Initial Temperature: It is the temperature (at point B) at which change in a sample weight reaches a magnitude detectable by the thermobalance. Final Temperature: It is the temperature (at point C) at which the change in sample weight reaches its maximum. Reaction Interval: It is the temperature difference between the beginning and the end weight of the sample i.e. section of the curve between points B and C.