1

POLYSTYRENE (PS)

Anilraj.lanka (PG/H/15002)

  

INDIAN INSTITUTE OF PACKAGING, HYDERABAD

November 2015

2

 OBJECTIVES OF THE PROJECT 

To understand

• basic chemistry of Polystyrene

• manufacturing aspects of polystyrene

• various design aspects of & their applications

• advantages and challenges.

• new developments in Polystyrene.

• how to overcome the problems in recycle Poly Styrene?

3

HISTORY

• Polystyrene was discovered in 1839 by Eduard Simon, an apothecary in Berlin.

• from storax resign of gum tree Liquidambar orientalis he a distilled an oily substance monomer that was named “styrol”.

• found that the styrol had thickened, from oxidation into a jelly he described that styrol oxide("Styroloxyd") i.e a polymerization process.

• In 1845 a chemist John Blyth and August Wilhelm von Hofmann showed that the

same transformation of styrol took place in the absence of oxygen.

• they called their substance metastyrol.

• in 1866 Marcelin Berthelot correctly identified the formation of metastyrol /Styroloxyd from styrol as a polymerization process

4

INTRODUCTION

Polymerization of Styrene gives Polystyrene

Structure of polystyrene

IUPAC name Poly(1-phenylethene)

Other names Thermocole

Identifiers

CAS Registry Number 9003-53-6

Properties

Chemical formula (C8H8)n

Density 0.96–1.04 g/cm3

Melting point ~ 240 °C (464 °F; 513 K) (decomposes at lower temperature)

Thermal conductivity (0.033 W/(m·k) (foam, ρ 0.05g/cm3)

Refractive index (nD ) 1.6; dielectric constant 2.6 (1 KHz–1 GHz)

GENERAL PROPERTIES

5

6

POLYSTYRENE IN BALL-STICK MODEL

Polystyrene consists of long hydrocarbon chains, with a phenyl group connected to every other carbon atom.

7

CHEMICAL STRUCTURE

**Polymerization is a process of reacting monomer molecules together in a chemical reaction to form polymer.

8

**Polymerization is a process of reacting monomer molecules together in a chemical reaction to form polymer.

Polystyrene consists of long hydrocarbon chains, with a phenyl group connected to every other carbon atom.

Polystyrene comes in three forms:

• Syndiotactic : it is highly regular and crystalline.

• Atactic : it is irregular and amorphous(disordered)

• Isotactic : it is semi-crystaline

 

POLYMERIZATION & TYPES OF POLYSTYRENE

9

POLYMERIZATION & TYPES OF POLYSTYRENE

10

GLOBAL CONSUMPTION, MARKETS & CAPACITY OF POLYSTYRENE

Annual production in 2014

World 14.6 million tones

Europe 3.4 million tones

US 4.0 million tones

Russia 0.27 million tones

Project report on Polystyrene 11

DIFFERENT FORMS OF POLYSTYRENE

HIPS

Oriented polystyreneExtruded polystyrene (XPS)

Expanded polystyrene (EPS) Packing peanuts

12

GENERAL PROPERTIES

• Polystyrene can be rigid or foamed

• Polystyrene is clear, hard and brittle

• It has low melting point (190ºF)

• Polystyrene can be naturally transparent.

• polystyrene is brittle, and hard

13

PHYSICAL & MECHANICAL PROPERTIES

PHYSICAL PROPERTIESDensity (g/cm³) 1.05Water Absorption, 24 hrs (%) 0.06Specific heat (c) 1.3 kj/ (kg·K)

MECHANICAL PROPERTIESTensile Strength (psi) 7,500Tensile Modulus (psi) 450,000Tensile Elongation at Break (%) 47

Flexural Strength (psi) 6,100Flexural Modulus (psi) 475,000Compressive Strength (psi) 14,500Hardness, Rockwell 75M-0.8

14

BARRIER PERFORMANCE OF MAIN PACKAGING POLYMERS

15

Easy to handle, Durable Strong & flexible

Easily molded, thermoformed and extruded into film.

It is extremely rigid yet lightweight, enhances food service sanitation

Low water absorption

Shock absorbent

Dimensionally stable

Recyclable

ADVANTAGES OF POLYSTYRENE

16

High Impact Polystyrene,

it is a tough, rigid plastic material with high impact strength.

It is widely used for toys, in packaging, signs.

It is a coloured plastic with good impact properties.

various shapes and objects can be produced from this material.

HIPS PROPERTIES

EPS PROPERTIES

Expanded polystyrene is a material of choice for versatility, and cost

effectiveness.

It is widely used in many everyday applications

It is a light weight and it is comprised of ~98% air. It has good strength.

It has thermal insulation and shock absorption characteristics provide high

performance of the products.

17

EPS vs CFB

EPS : EXPANDED POLYSTYRENE

CFB : CORRUGATED FIBER BOARD

18

Packaging  : Food products and cold drinks or carry-out meals. polystyrene is a versatile and cost-effective solution for rigid packaging

and food service disposables.

Consumer electronics : leading choice for media enclosures, cassette tape housing and clear

jewel boxes, to protect CD's and DVD's.

Construction: Polystyrene resins are the most popular materials for building and

construction applications

Medical: PS is used for a wide range of disposable medical applications,

including tissue culture trays, test tubes, petri dishes, and housing for test kits.

Cosmetics containers for talcum powder, cream, shaving soap, tooth powder,

hair cream, kajal, lipstick, etc.

APPLICATIONS OF POLYSTYRENE

19

Extruded polystyrene is usually made with hydrofluorocarbons (HFC-134a), which have global warming potentials of approximately 1000–1300 times that of carbon dioxide.

Non-biodegradable: Discarded polystyrene does not biodegrade for hundreds of years and is resistant to photolysis.

Hazardous if improperly burnt: When burnt below 900 C up to 90 ⁰ dangerous compounds can be released (ex: alkyl benzenes,carbon monoxide)

The styrene monomer cancer causing agent.

ENVIRONMENTAL HAZARDS

20

RESIGN IDENTIFICATION CODE FOR RECYCLING OF POLYSTYRENE:

Recycling number

Image Unicode symbol

AlternateImage #

AlternateImage 0#

Abbreviation Polymer name

06

PS polystyrene

21

RECYCLING AND ITS ADVANTAGES

• Using recyclables rather than raw material to make new products:

• Could use less energy

• Could result in less pollution

• Saves natural resources

• Saves scarce landfill space

• Could reduce littering

• Could create extra income and jobs

22

REFERENCES

• Fundamentals of packaging technology by Walter Saroka

• https://en.wikipedia.org/wiki/Polystyrene

• http://plasticfoodservicefacts.com

• http://www.plasticseurope.org

• http://www.earthresource.org

• http://www.plasticseurope.org

• http://www.ihs.com

23

THANK YOUAnilraj.lanka (PG/H/15002)