Introduction to Polymer Processing

Introduction to Polymer Processing

CBE 4009 Polymer Processing – Introduction to Polymer Processing

the operations carried out on polymeric materials or systems to increase their utility

Chemical operationPhysical operation

Machine and Equipment DesignPlant Design and OperationsProduct Development: the physical and chemical evaluation

of materials


Polymer Processing

Shaping(Froming) Extrusion(압출성형), Coextrusion(공압출성형), Calendering, Blown film, Fiber Spinning, Injection Molding(사출성형), Compression Molding(압축성형),Blow molding(중공성형), Thermoforming(열성형),Resin transfer molding(수지이동성형), Pultrusion, Casting,

BondingHeat sealing, Laminating, Coating

ModificationMixing and Compounding, Surface activation, Polymer modification(crystallization and orientation)

Post ShapingStructuring, Decorating, Fastening, Sealing, Welding, Dyeing, Electroplating, Vaccum metallizing, Printing, Painting, etc.


Classification of Polymer Processing

성형공정에따른플라스틱의소모비율

Polymer and Additives

FeedPreparation

Feeding

Conveying Melting PumpingMixing

FormingCoolingand Post-FormingOperations

Heat

Mec

hani

cal E

nerg

y

Pro

duct

T tP tG tX t

( )( )( )( )

Extruder Mold or Die

Product• Film• Sheet• Moldings• Bottles• Fibers• Coated Wire• Pipe

Fig. . Schematic of Generalized Extrusion Process


Fig. Sectional view of a single screw plastic extruder and various types of screw


Fig. Schematic view of an inverted L calender plant for the production of plastics sheeting

extruder


Fig. Schematic view of a film blowing operation

extruder



Coextrusion film

Stage 1. InjectionMold partially filled

Feed hopper

Barrel

Heater band

Screwadvances

Stage 2. Holding Pressure and Plastication

Screw rotatesat the end ofholding

Stage 3. Ejection

Mold opens and part is ejected

Nozzle breaks off

Mold filled and part is cooled

Fig. Schematic representation of injection molding process.



Extrusion Blow molding


Stretch Blow Molding

Initial Step.Thickness Distribution

PET stretch blow molding simulation


The pressure P1(18bar) is applied to the inside of preform.

Thickness Distribution


The plug startsto push the preform.

(V=92.5cm/s)





P2(32bar) is applied











The plug reached bottle base

























Fig. Twin sheet thermoforming process


(b)

(a)

Preform placement Resin injection and cure Part removal

A B

Ratiocontrol

Mixer

Monomer B

Monomer A

Poly

mer

izin

g m

ixtu

re

Mold

RRIM(milled fiber)

SRIM(fiber mat)

Fig. 1. Schematics of liquid composite molding (LCM) process. (a) resin transfer molding (RTM) (b) structural reaction injection molding (SRIM)


Fig. Schematic diagram of pultrusion process


Fig. Schematic of a forward roll coating and magnified view of the nip region (a) a flooded inlet (b) a starved inlet


Intrinsic material

properties

Processingproperties

Articleproperties

Material Processing Article

+ =

Machinery inprocess industry

Objectivestandard

Subjectivestandard

Interrelationship between Processing and Property


Process-Structure-Property Relationships

Processing

Thermal history Stress/Strain history

Chemical modification

Structure

CrystallinityCrystal size and structure

OrientationResidual stress/strain

Property

MechanicalOptical

ChemicalSolid state


ELE

ME

NTA

RY

STE

PS

Structuring of Polymers in Processing

Mixing

Handling ofParticulate Solids

Pressurization& Pumping

Devolatilizationand Stripping

Melting

Mold Coating

Calendering & Coating

Secondary Shaping

Molding & Casting

Die Forming

TransportPheonomena

Mixing Principles

SolidMechanics

Polymerchemistry

PolymerPhysics

PolymerRheology

Engineering Principles Polymer Science

SH

AP

ING

ME

THO

DS

PO

ST

SH

AP

ING

A STRUCTURAL BREAKDOWN OF POLYMER PROCESSINGRaw

MaterialFinishedProduct


The Historical Evolution of Polymer Processing

Time Frame

1850-1950 1950-2000 Transition (present) Future

Rubber and Plastic Technology

Classical Polymer Processing

Polymer Processingfor Structuring

Macromolecular Engineering

FocusProduct machine invention

Process and machine design

Product design(micro-structuring)

New products and structuring

“Pushing the Limits”

Discipline Inventive praxis

Transport phenomenaGNF rheologyComputational fluid

mechanics

Transport phenomenaFull rheologyMelt/solid physicsInterfacial phenomenaPolymer chemistryIn-line characterizationThermodynamics

Macromolecular physics, chemistry, rheology

Multiscale transport and computation

Molecular scale probe

BenefitsNew class of materialsNew industry

Ability to process very diverse polymers

Customized structure/properties

Value-added materials

New generation of globally applicable polymer

Truly advanced polymer

Documents

Introduction to Polymer Processing