chemically resistant fibers

8/8/2019 Chemically Resistant Fibers

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PRESENTATIONHigh performance fiber



SUBMITTED BY :-

Mu hammad Mu ddaser Sharif

° 07-NTU-87



P resented to : -

SIR UZA IR Sb



TITLE :-

Section A

´ C hemically Resistant Fibers´ PEEK

´ PP S´ PE I



INTRODUCTION:-

´ D efinition« C hemically resistant organic polymeric fibers

inclu

de those which are designed to resistchemical attack for acceptable period d u ring there service lives and both ambient andelevated temperat u res



´ Some chemical resistant fiber

1. Aramids2. Arimids



STRUCTURE:-

´ These fibers are inert d u e to1. Strong bonding system within the polymeric

backbone2. P resence of no or nonreactive side gro u ps3. D u e to the aliphatic chain hydrogen atoms

increases the tendency of Oxidation so

there presence sho u ld be minim u m



EFFECT OF OXIDIZING AGENT:-

´ The fiber from polyethylene and

polypropylene have acceptable resistance tomany chemicales at ambient temperat u reb u t resistance decrease when atemperat u re reaches at 5 0 c



´ E specially when oxidizing agent are

present the chemical resistance of fiber is decreased



EFFECT OF FUNCTIONAL GROUP:-

´ The polymer backbone sho u ld be free of hydrolysable f u nctional gro u p

1. E ster

2. Amide



´ The fiber based on aliphatic polyamide andpolyester str u ct u res lack s u fficient chemicald u rability



FUNCTIONAL GROUP :-

´ The f u nctional gro u p which enhancethechemical resistance or chemical d u rability

1.A

romatic analog u

es2. P oly aramids´ Show greater resistance



PEEK

´ It is abbreviation of poly

(etheretherketones)



INTRODUCTION:-

´ It is the foremost member of the family of semicrystalline aromatic thermoplastic polymer



POLYETHER KETONES (PEKS )

´ It is capable of being formed into an extensiverange of mono filaments and fiber u sing hightemerat u re melt spinning techniq u es



STRUCTURE :-

´ PEE k has a polymer repeat u nit of one ketoneand two ether gro u ps

´ This provides a linear f

ully aromatic highlystable , str u ct u re containing only carbon ,

hydrogen and oxygen



PEEKSTRUCTURE

c

On



HISTORY :-

´ Some experiments were carried o u t in 199 0· s´ It is first man u fact u red and commercialized by

IC

I advance material in the late 1970·

s andearly 19 80· s u nder the brand name VI C TREX PEEK



´ The amphasis was on injection mo u lding application b u t work by I C I and L EE D Su niversity showed the polymer ·s potentials forprod u cing high specification fiber .

´ Other man u fact u rer introd u ced pilot plantdevelopment of competitive polyether ketonesthro u gh the 19 80· s



MANUFACTURERS :-

´ M an u fact u rers of polyether ketones are

1. PEKEKK by B ASF

2. PEKK by D u P ont3. PEEKK by Hoechst



´ Tg (glass -ru bber transition temp)AN D Tm (melting point) of polyether ketone



Tm °cTg °cpolymer

334143PEEK

36515 0PEEKK

365152PEK

3 8 1170PEKEKK

391165PEKK



SECTION B



PEE k fiber P erformance

factors :-



´ Temperat u re performance´ C hemical inertness

´ Abrasion resistance´ D imensional stability´ P olymer p u rity



´ Flammability´ P rocess ability

´ Su stainability



DETAILS :-

´ Temperat u re performance« A contin u es operating temperat u re for many

application of u p[ to 26 0 °c with short ex cu rsionsto 300 °c being possible , and non brittle lowtemp performan ce down to -60 °c



´ C hemical inertness« It is u naffected by high temp steam and most fl u id

and chemical reagent



´ Abrasion resistance« It has a to u gh, low friction, low wear , c u t resistant

s u rface and is partic u larly good at resisting abrasion at elevated temp and relatively highs u rface speed.



´ D imensional stability« It exhibits low creep and low shrinkage especially

below its Tg (143 °c) , it has ex cellent dynami c re covery and flex fatig ue performan ce



´ P olymer p u rity« are exceptionally p u re, witho u t the need for

stabilising additives, and they have EEC and F D A

approval for medical 26 8 High -performance fibres



TABLE PROPERTIES OF PEEK

Valu e/parameterP ropertyBeige (thick section)C olo u r

1.3 0Specific gravity

334M elting point,

143Glass transition, T g,

3 0² 35C rystallinity, %

0 .1M oist u re regain, 65% rh 2 0 ° C ,

19 0D ielectric strength, kV/cm

1 0 16Resistivity, ohm -cm1.34Heat capacity, kJ/kg/° C

0 .25Thermal cond u ctivity, W/m/° C



´ Flammability« fibres are self -exting u ishing with an LOI of 35%

while emitting one of the lowest levels of smokeand toxic gases.



´ P rocess ability« the room temperat u re physical properties of PEEK

fibres are similar to those of both polyester andnylon, so textile processes s u ch as weaving andbraiding can be conveniently performed



´ Su stainability« recovery and recycling of PEEK as a material can be

carried o u t u nder certain conditions with little lossof key physical properties.1 8



FIBRE PRODUCTS

Starting in the early 19 80 s, a n u mber of companies set o u t to prod u ce PEEK fibres of vario u s different types for commercial sale.

Initially, circ u lar cross -section monofilaments inthe diameter range 0 .4 to 1. 0 mm were extr u ded athigh temperat u re, cooled, drawn and relaxed togive lowshrinkage prod u cts with physical

properties in the range0

.3 to0

.4N

/tex tenacityand 3 0 to 4 0 % extension -to -break, with hot -airshrinkages belo 2% at 1 80 ° C .



´ Finer individ u al monofils and progressivelyfiner m u ltifilament yarns down to 1 00 dtex andfilament finenesses of 3 dtex (2 0 mm) havebeen refined thro u gh the 199 0 s, yielding f u rther improvements in tenacity.



´ Additionally, a wider range of cross -sectionaltypes, incl u ding rectang u lar and hollowfilaments and an increasing range of colo u rpigmented monofilaments, have becomeavailable for the main monofil diameters ( 0 .2 0 to 1.5 0 mm).



MANUFACTURER :-

´ ZY EX Limited´ Teijin´ K

osa´ Shakespeare´ Lu xilon

´ Albany International



FIBRE PROPERTIES

% Strength retainedFibre

Temperat u re3 00 ° C25 0 ° C2 00 ° C15 0 ° C

9 0951 001 00PEEK

07 5951 00m -aramid

M elted09 01 00PP S

melted03 09 0PE T



PEEK AND OTHER FIBRES EXPOSED FOR 7 DAYS INPRESSURISED STEAM

% Strength retainedFibreTemperat u re

3 0025 02 0015 01 00

80951 001 001 00PEEK

disintegrated09 01 001 00PP S

0009

01

00M -aramid

disintegrated0009 0PE T



CYCLES TO FAILURE FOR PEEK AND OTHER FIBRESAS THREADS ± THREAD ON THREAD ABRASION AT 120 °C

C ycles to fail u reFibre

9 00PEEK

6 00P A

5 00PE T

25 0M -aramid

5 0PP S



FIBRE APPLICATIONS

´ Applications relate to ind u strial and technicalend -u ses where a combination of good physicalproperties and inertness to the environmentare essential feat u res:



PROC ESS CONV EY OR BELTS :

´ The mainstream application for PEEK fibres isin ind u strial conveyor belts that carry prod u ctthro u gh aggressive processing stageseffectively on a contin u ou s basis, in partic u lar,in the man u fact u re of paper or nonwoven fabricprod u cts where pressing, bonding or drying

stages can involve temperat u res u p to 3 00 ° C at line speeds u pto 3 00 m/min



PR ESS FILTE R S

´ Fine woven screens of PEEK are u sed in framefilters, or slow -moving press filter applicationsfor the prod u ction of board prod u cts or thedewatering of chemical powders. D imensionalstability and the ability to s u rvive many morepress u re cycles than eq u ivalent metal screens

are important here.



PRO TE C TI V E B R AIDS

´ PEEK braids, made mainly fromcolo u red/pigmented monofils are increasinglyimportant in aerospace, a u tomotive and ind u strialapplications. In partic u lar, the additional chaferesistance and temperat u re stability delivered areideal for electrical wiring looms associated withengine components in aircraft and motor vehicles.In addition, in any enclosed sit u ations where toxic

f u

mes from bu

rning wiring cou

ld pose a threat tolife, PEEK as a cable covering is ideal



R EI N F ORC ED RU BBE R GASKETS

´ A m u ltifil PEEK scrim fabric is u sed toreinforcesynthetic r u bber gaskets and bellows.The fibre ·s u niq u e combination of good flexfatig u e performance and resistance to thechemical breakdown prod u cts of the r u bber athigh temperat u re greatly extends component

lifetime in specialised applications.



I N D U ST R IAL B R ISTLES

´ Bru sh bristles u sed for hot -cleaning extr u dersand injection mo u lds are sometimes preferredas PEEK monofils, rather than soft metal wires.



PRO TE C TI V E C L O THI N G

´ Mu ltifil PEEK sewing threads have fo u nd nichemarkets in ind u strial protective clothing,associated with their chemical inertness. Also,hook and loop fasteners u tilising both monofiland m u ltifil PEEK prod u cts are u sed in q u ick -

release garments in hightemperat u re

environments.



S POR TS ST R I N GS

´ The possibility of man u fact u ring fibres thatexhibit deformation and rapid recovery fromhigh stress rates has given rise to PEEK ·s u sein u p -market tennis, sq u ash and racq u et ballstring



M U SI C ST R I N GS

´ The u niq u e tonal q u ality and tension -holding that can be achieved from specified PEEK prod u cts have given rise to their adoption forg u itar, violin and other stringed instr u ments



THE R M OP LASTI C CO M PO SITES

´ PEEK fibres can also be u sed as a so u rce of the matrix in composites. Intimately mixed withcarbon fibres, PEEK fibres provide an idealfeedstock for the prod u ction of advancedthermoplastic composites. In the press u risedhigh -temperat u re mo u lding



POLY(ETHER IMIDE), PEI

´ Like PEEK , poly(ether imide) is really anengineering plastic which has fo u nd applicationas fibres in some applications where chemicaland temperat u re resistance are req u ired.Altho u gh its temperat u re resistance isslightlyinferior to that of PEEK , PE I is a cheaper

material.



MANUFACTURER :-

´ Teijin´ Acordis (formerly Akzo)



PROPERTIES :-

´ PE I is essentially an amorpho u s polymer whichmay be melt -sp u n to yield fibres having onlymoderate tenacities ( 0 .25 N / Tex)

´ breaking elongations of abo u t 4 0 %.



´ Fibres can resist temperat u res u p to 19 0 ° C forlong periods and also possess high LOI val u e of 45%



COMPARISON OF PROPERTIES OF PEI WITH PPS AND PEEKFIBRES33

Tensilestrength, N /tex

LOI, %T max, ° C T m, ° C Fibre

0 .192 -2444 -45170- 19 0215-225PE I

0 .453419 0285PP S

0 .6 0-0 .653526 0- 3 00234PEEK



CHEMICAL RESISTANCE OF PEIFIBRES

Strength retentionafter 15 00 h at 2 0 ° C , %

C oncentrationC hemical

1 0 11 0 %Hcl

991 0 %HN O3

9510

%H2SO41 0 61 0 %HF

1 0 41 0&C H3 C OOH

1 0 1Sat u ratedN a C l

1 0 4M ineral oil

11 0pH 9Borax

1 0 4pH 1 0(N H4)3 P O4

96pH11N H3

1 07pH 12.5C a(OH)2

84pH 3,5

NaOH



THAN K S

chemically resistant fibers

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