powerpoint - new stabilization package for controlled ... · new stabilization package for...

New Stabilization Package for Controlled Rheology Polypropylene Fibers

(Benchmarked against Phenol & Phenol-free Systems)

SPE International Polyolefins Conference 2012

J. Mara 1, H.-J. Kwon 2, J.-D. Kim 2, J. Bayer 3 & K. Keck 2

1 Songwon International Americas; USA 2 Songwon Industrial, South Korea

3 Songwon International, Switzerland

• Introduction to Auto-oxidation of Polyolefins • Degradation of Polypropylene (PP) • Classification of PP Fibers (by Songwon)

Stabilization Requirements for PP Fibers Stabilization Strategies for PP Fibers Technical Benchmarking vs. Phenol-containing & Phenol-free Systems Summary

Contents



OH

H2O

O2

OO*

Peroxy Radical

OOH

Hydroperoxide

*

Alkyl Radical

O*

HO *

Alkoxy Radical

Hydroxy Radical

Polymer

Polymer

Polymer

None Radicalic Products

Oxygen Heat

Shear UV

Metal Ion (Mn+)

Heat UV

Simplified Auto-Oxidation Cycle of Polyolefins

Introduction

Concepts to Counter Auto-Oxidation of Polyolefins

Free Radical Scavenging

Phenolic Antioxidant + → +

Aminic Antioxidant + → +

Peroxide Decomposition

Phosphite Antioxidant + → +

Thioester Antioxidant

+ → + + → +

OH

B A

C

OO* O*

B A

C

OOH

N H

R

OO* * N R

OOH

P OR

OR

RO

OOH P OR

O

RO

OR

OH

S R R

OOH

S R

O

R

S R

O

R

O

OH

OH

S R

O

R

OOH

Introduction

SPE International Polyolefins Conference

OH

H2O

O2

OO*

Peroxy Radical

OOH

Hydroperoxide

*

Alkyl Radical

O*

HO *

Alkoxy Radical

Hydroxy Radical

Polymer

Polymer

Polymer

Oxygen Heat

Shear UV

Metal Ion (Mn+)

Heat UV

Radical Scavenging HALS, Amine ?

Radical Scavenging HALS, Amine, AO

Radical Scavenging HALS, Amine, AO

Radical Scavenging

Auto-Oxidation Mechanism Thermo-Oxidation

Peroxide Decomposition

Phosphite, Thioester


Introduction

• PP is an unstable substrate • Industrially unsuitable w/o stabilizers • Undergoes uncontrolled thermo-oxidative degradation w/o stabilizers • Polymerization, processing, & service life conditions can vary …

Degradation of Polypropylene


PP will undergo different Degradation Mechanisms: • Processing/Conversion:

• Concentration [ROO*] < Concentration [R*] • MW decreases; [Mw/Mn] narrows • Disproportioning of Alkyl Radicals (formation of c=c)

• Storage/Service Life: • Concentration [ROO*] >> Concentration [R*] • MW decreases; [Mw/Mn] broadens • Formation of Carbonyl Groups

• Different & Contradicting Stabilizer Reqirements

Degradation of Polypropylene


Classification of Polypropylene Fiber

• PP fiber grades are supplied over a range of MW’s depending upon processing & conversion characteristics as well as required properties of the application.

• Songwon classifies PP fiber grades by the conversion technology & by the presence (or absence) of peroxides for controlled degradation (Controlled Rheology).

• Monofilament & Tape grades have low MFI’s which need to be maintained during compounding & conversion.

• Meltblown & Spunbond grades have MFI’s that must be tailored in a post reactor operation via the use of peroxides (CR grades).

• Bulk continuous filament & Staple grades are available as either reactor grades or CR grades.

0 10 20 30 40 50 60 70 80

Melt Flow MFI 230°C/2.16

Monofilament

Slit Tape

Staple Fiber

Continuous Filament

Spunbond

Meltblown

Typically cracked

- 1500

Can be cracked

Reactor grade

Narrow

Narrow

Normal to narrow

Normal to broad

Normal

Normal

1-Step CR 2-Step CR


Classification of Polypropylene Fibers


0 10 20 30 40 50 60 70 80


Reference: E.P. Moore; Polypropylene Handbook; Hanser Publishers (1996)

Monofilament

Slit Tape

Staple Fiber

Continuous Filament

Spunbond

Meltblown - 1500

Reactor grade

Narrow

Narrow

Normal to narrow

Normal to broad

Normal

Normal



0 10 20 30 40 50 60 70 80



Monofilament

Slit Tape

Staple Fiber

Continuous Filament

Spunbond

Meltblown - 1500

Can be cracked

Reactor grade

Narrow

Narrow

Normal to narrow

Normal to broad

Normal

Normal



0 10 20 30 40 50 60 70 80



Monofilament

Slit Tape

Staple Fiber

Continuous Filament

Spunbond

Meltblown

Typically cracked

- 1500

Can be cracked

Reactor grade

Narrow

Narrow

Normal to narrow

Normal to broad

Normal

Normal

1-Step CR 2-Step CR

Standard Post Reactor Extrusion


Stabiliser & Peroxide Addition for CR-PP

W W

Peroxide (mainly liquid)

Stabiliser Single Additive, OPS

or masterfluff

Loss-in-weight feeder

(Individual) additive streams

Polyolefin bulk feed

Polymer main stream

High shear extruder Pelletizing & Storage

Silo or discharge hopper

P

Storage tank

Pump

Separate Addition during Extrusion


Stabiliser & Peroxide Addition for CR-PP

W W

Peroxide (mainly liquid)

Stabiliser Single Additive, OPS

or masterfluff

Loss-in-weight feeder

Stabiliser stream (later)

Polyolefin bulk feed

Polymer main stream

High shear extruder Pelletizing & Storage

Silo or discharge hopper

P

Storage tank

Pump

Peroxide stream (first)

Stabilization Requirements of PP Fibers


• Excellent MW protection during compounding & conversion – Principle reason for addition of processing stabilizer

• No interaction with peroxides (CR grades)

– Peroxide interaction leads to strong antagonism w/processing stabilizer

• Low initial color following compounding • Low color development following conversion • Low gas fade during conversion & storage

– Potentially negatively affected by primary AO

• Adequate storage stability (optional) • Outdoor UV stability (optional)

– Easily adjustable by choice of HAS

• Other (registrations, cost, industrial availability)

Stabilization Requirements of PP Fibers

• Performance requirements for PP fiber stabilization packages vary with the conversion technology & the need for CR grades.

• An overview of the importance of the various requirements for the different PP fiber grades is given below:

Com

poun

ding

Con

vers

ion

Serv

ice

Life

Mon

ofila

men

tTa

pe

Stap

le (R

eact

or)

(B) C

F (R

eact

or)

Stap

le -

CR

(B) C

F-C

R

Spun

bond

-CR

Mel

tblo

wn-

CR

Remark

Excellent MW Preservation P P

Low Peroxide Interaction P P

Low Initial Colour P P

Low Colour Development P P P

Low Gas Fading P

Low Smoke & Fume P

Good MW Protection- LTTS P

Good MW Protection - UV P

Very important Suitable; usually required Required or not depending on end application

Depending on end application

Only colour critical applications


SPE International Polyolefins Conference 2012 February 26th - February 29th, 2012

Stabilization Strategies for PP Fibers


3 Alternatives for PP Fibers

Grade Compounding Fiber Conversion Stabilization Strategy

Reactor MW Preservation MW Preservation Excellent ProcessingStability

1 Step CR Controlled MW Decrease MW Preservation Optimum Balance of Good Processing Stability

vs. Low Peroxide Interaction

2 Step CR Controlled MW Decrease Controlled MW Decrease No or MinimalProcessing Stability


Selection Guide for PP Fiber Grades

Criteria

Classification Songwon Product (ppm)

Exce

llent

MW pr

eserv

ation

Low

perox

ide in

terac

tion

Low

initia

l colo

r

Low

color

deve

lopme

nt

Low

gas f

ading

Low

Fume

& S

moke

Good

MW

prote

ction

-LTTS

Good

MW

prote

ction

-MI

Remarks

Songnox 21B (1500 ~ 2000) ● ○ ○ ○ Not suitable for color sensitive

applications Monofilament & Tape

Songnox 1790 + Songnox 6260 [33:67](1000~1500) ● ○ ● Severe processing condition

Songnox 21B (1500 ~ 2000) ● ○ ○ ○ Not suitable for color sensitive

applications

Songnox 331B (1500 ~ 2000) ● ○ ● ○ ○ ○ Offers improved color

Staple - Reactor Continuous Filament (CF) - Reactor

Songnox 3016 GR (1000 ~ 2000) ● ○ ● ● ● ● ● Offers best color

Songnox 331B (1500 ~ 2000) ● ○ ● ○ ○ ○ Offers improved color Staple - CR

Continuous Filament (CF) - CR Songnox 3016 GR

(500 ~ 1500) ● ○ ● ● ● ● ● Best color, Excellent balance MW preservation & Low peroxide interaction

Songnox 331B (1000 ~ 2000) ● ○ ● ○ ○ ○ Offers improved color

Spundbond Songnox 3016 GR (500 ~ 1500) ● ○ ● ● ● ● ●

Best color, Excellent balance MW preservation & Low peroxide interaction

Meltblown Songnox 3016 GR [1:1] (300 ~ 600) ● ● ● ● ● ○ ○

No peroxide interaction Very good color & gasfading Low Fume & Smoke

● Recommended / Fulfills criterion completely / ○ Can be used [Green: very important / critical (in general), Yellow: very important / critical (selected end application) Gray: important / useful]

• Recommendations are grouped around the conversion technology & corresponding importance of stabilizer requirements as captured in previous slide.

Songnox 3016 Characteristics • New AO package for color critical applications, including:

– PP Fiber (Bulk Continuous Filament – Reactor & CR; Staple – Reactor & CR; & Spunbond applications)

– Polyolefin Film applications (Not covered today) – Polyolefin Tape applications (Not covered today) – Thin Walled Injection Molding (TWIM) applications (Not covered today)

• Provides an excellent balance between Processing Stability & Low Peroxide

interaction.

• The interaction with peroxide is significantly reduced compared to Phenol containing systems (i.e., Songnox 321B) & Phenol-free systems, including:

– Irgastab FS 533 (Composition: FS042 + I-168 + C-2020) [1:10:3] – Irgastab FS 102 (Composition: FS042 + I-168 + T-622) [1:2:1]

– Irgastab FS 410 (Composition: FS042 + C-944) [1:1] • Performance data in PP homopolymer (gas phase) / MFI(230 C/2.16 kg) ~4 to 6

[dg/min] follows…


Substrate: PP homopolymer (gasphase) MFI 230/2.16 ~ 4 to 6 [dg/min] Compounding: N2, 190 – 215oC, TS Criterion: MFI after compounding

Stabilisation: 500 ppm Ca-stearate + 1000 ppm stabiliser Additivation: 490 ppm PO-4 [2,5-Bis(t.-butylperoxy)-2,5-dimethylhexane]

Stabilizer Interaction with Peroxide in CR-PP

4 8 12 16 20 24 28 32

MFI (g/10min) 2.16kg/230oC

No additive

Songnox 3016 GR

Songnox 321B

Irgastab FS 102

Irgastab FS 410

Irgastab FS 533


Substrate: PP homopolymer (gasphase) MFI 230/2.16 ~ 4 to 6 [dg/min] Compounding: N2, 190 – 215oC, TS Exposure: 5hr at 60oC under 5% NOx gas (KS K 0454)

Stabilisation: 500 ppm Ca-stearate + 1000 ppm stabiliser Additivation: 490 ppm PO-4 [2,5-Bis(t.-butylperoxy)-2,5-dimethylhexane] Criterion: Delta YI

Low Gas Fading in CR-PP

Songnox 3016 GR

Songnox 321B

Irgastab FS 102

Irgastab FS 410

0 5 10 15 20 25 30

Delta Yellowness Index

Irgastab FS 533


Substrate: PP homopolymer (gasphase) MFI 230/2.16 ~ 4 to 6 [dg/min] Compounding: N2, 190 – 215oC, TS

Stabilisation: 500 ppm Ca-stearate + 1000 ppm stabiliser Additivation: 490 ppm PO-4 [2,5-Bis(t.-butylperoxy)-2,5-dimethylhexane] Criterion: YI after compounding

Low Initial Color in CR-PP

-4.0 -3.8 -3.6 -3.4 -3.2 -3.0

Yellowness Index E 313

Songnox 3016 GR

Songnox 321B

Irgastab FS 102

Irgastab FS 410

Irgastab FS 533


Substrate: PP homopolymer (gasphase) MFI 230/2.16 ~ 4 to 6 [dg/min] Compounding: N2, 190 – 215oC, TS

Stabilisation: 500 ppm Ca-stearate + 1000 ppm stabiliser Additivation: 490 ppm PO-4 [2,5-Bis(t.-butylperoxy)-2,5-dimethylhexane] Criterion: YI after multiple extursion Pass 1 ~ 5

Low Color Development during Processing

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0

Yellowness Index E 313

Pass 5

Pass 3

Pass 1

Songnox 3016 GR

Songnox 321B

Irgastab FS 102

Irgastab FS 410

Irgastab FS 533


Stabilisation of Controlled Rheology Polypropylene Methodology

Radar chart Relative scale: 5 Best (outside)

4 3 Intermediate 2 1 Worst (inside, center)


1

2

3

4

5Excellent Processing Stability

Low Peroxide Interaction

Low Initial Colour

Low Colour Development (Processing)

Low Gas fading

Easy Adjustment LTTS / UV

Stabilisation of Controlled Rheology Polypropylene


1

2

3

4

5Excellent Processing Stability

Low Peroxide Interaction

Low Initial Colour

Low Colour Development (Processing)

Low Gas fading

Easy Adjustment LTTS / UV

Stabilisation of Controlled Rheology Polypropylene Unstabilised Controlled Rheology PP


Formulation:

Stabilisation Strategy:

Positioning:

General Phenol Stabilizer System A

A [Songnox 317B] Composition: 3 parts SN1680 + 1 part SN1076

[Phenolic AO + Phosphite] synergism Standard phenolic AO Standard phosphite Partially optimised composition & ratio

Standard AO package from IM or extrusion



A [Songnox 317B] 1000 ppm


Formulation:


Positioning:

General Phenol Stabilizer System B

B [Songnox-321B] Composition: 2 parts SN1680 + 1 part SN3114

[Phenolic AO + Phosphite] synergism Phenolic AO with reduced color formation Partially optimised composition & ratio

Improved processing stability



A [Songnox 317B] 1000 ppm B [Songnox 321B] 1000 ppm


Formulation:


Positioning:

Phenol-Free Stabiliser System C

C [Hydroxylamine + HAS / FS 410]

Elimination of phenolic AO (color source) Processing stability based only on hydroxylamine No synergistic effect Conversion independant of service life

Hyperactive processing stabiliser



A [Songnox 317B] 1000 ppmB [Songnox 321B] 1000 ppm C [FS 410] 1000 ppm


Formulation:


Positioning:

Phenol-Free Stabiliser System D,E

D [Hydroxylamine + Phosphite + HAS / FS 102] E [Low hydroxylamine + Phosphite + HAS / FS 533]

Elimination of phenolic AO (colour source) ‘‘Kinetic’’ balance Processing vs. Peroxide Synergistic effect Conversion independant of Service Life

C System formulated with low level of hyperactive

processing stabiliser



A [Songnox 317B] 1000 ppm B [Songnox 321B] 1000 ppm C [FS 410] 1000 ppm D [FS 102] 1000 ppm E [FS 533] 1000 ppm


Formulation:


Positioning:

New Color Critical Stabiliser System

F [Songnox 3016 GR]

Elimination of phenolic AO (colour source) ‘‘Kinetic’’ balance Processing vs. Peroxide Synergistic effect Conversion independant of Service Life

No hyperactive processing stabiliser



A [Songnox 317B] 1000 ppm B [Songnox 321B] 1000 ppm C [FS 410] 1000 ppm D [FS 102] 1000 ppm E [FS 533] 1000 ppm F [Songnox 3016] 1000 ppm



Summary

• PP in general must be stabilized during compounding, processing, storage, and service life.

• The stabilization of CR-PP during compounding and conversion is rather complex.

• While efficient protection of the PP is easily achievable via stabilizers with high molar activity & reaction kinetics, peroxides may also be added in order to degrade the PP in a controlled manner, yielding grades with lower MW & narrower MWD’s.

• In this work, we introduced a powerful new AO package for CR-PP that provides excellent balance between processing stability, color suppression, and low peroxide interaction.

• While the scope of today’s presentation was limited to CR-PP fiber applications, the technology is also applicable to other applications such as TWIM where low peroxide interaction and low color development are critical.

powerpoint - new stabilization package for controlled ... · new stabilization package for...

Documents