Intro to PVDF Coating

Hylar 5000®

What The Initials Stand For:The full name is polyvinylidene fluoride, somethingonly chemists can say with ease. And even they preferto use the initials PVDF. Confusingly, the same materi-al is also known as PVF2, and categorized as a fluoro-carbon or fluoropolymer. Thus PVDF is a member of aclass of fluorine-based polymers. Other fluoropoly-mers include polytetrafluoroethylene (PTFE) andpolyvinyl fluoride (PVF).

What The Fluoropolymers Have In Common:Stability. The stability of fluoropolymers is the key factor in their unusual performance.

How PVDF Differs From Some Other Fluoropolymers:Modifying and copolymerization of fluorinated materi-als can result in diverse properties, uses and applica-tions. On the molecular level, PVDF differs from PTFEin that two of the carbon-fluorine bonds have beenreplaced by carbon-hydrogen bonds, as shown here:

The combination of carbon-fluorine bonds (providingstability) with carbon-hydrogen bonds creates aunique structure with balanced properties that makesPVDF particularly suitable as a base for liquid coatings.

How PVDF is Produced:The raw materials of PVDF are hydrogen fluoride andmethyl chloroform, which when reacted make a refrig-erant gas, chlorodiflouroethane of R-142V. Furtherprocessing of R-142B produces a vinylidene fluoridemonomer. Polymerization of the vinylidene fluoride, in high-purity water under controlled temperature andpressure with a catalyst, produces the PVDF polymer.Subsequent processing steps-washing, drying, finish-ing-produce the commercial powder resin.

The powdered PVDF resin serves as the base materialfor formulation of premium liquid coatings applied tometal architectural components. Pelletized PVDF is used

widely for processing into chemical process fluid han-dling systems and components, and various film andsolid items and parts where high performance is a concern.

Ausimont produces HYLAR 5000 PVDF at its plant inThorofare, New Jersey, the most advanced PVDF pro-duction facility in the world. Highly automated, theThorofare complex, which began operation only in1986, was designed and engineered to take advantageof the latest computer control and monitoring equip-ment. Virtually the entire process, with its various con-trols, is driven by computer programs, assuring a highdegree of quality and consistency.

To Make a PVDF Coating:Ausimont supplies the HYLAR 5000 PVDF powder,which is the key ingredient in the formulation of premium architectural coatings. Using this resin as abase, coatings manufacturers produce the coating systems. Ausimont works closely with the coatingsmanufacturers it supplies, sharing its own technologi-cal resources and experience.

A liquid coating is formed from the HYLAR 5000 pow-der by dispersing it in a latent solvent system. Thisdispersion is unaffected by ambient temperatures butwhen heated the powder particles dissolve and coa-lesce. By manipulating the solvent balance, a stabledispersion is produced that can be handled andapplied much like standard liquid coatings, and thenheat-cured into adherent integral films.

The Coatings formulation includes other ingredients,such as pigments for color and opacity. In addition,modifyers and additives may be added to achieve various specific properties.

Some Pigmentation Requirements:Since PVDF itself is transparent to and unaffected byultraviolet radiation, the pigment in the PVDF coatingmust be opaque to protect the substrate from thesun’s damaging UV radiation. To compliment the stability of PVDF, pigments should also be resistant toheat (since the coating must be baked), chemicals, andweathering. In general, non-organic color compounds,often known as ceramic pigments, exhibit these properties.

All statements, information, and data presented herein are believed tobe accurate and reliable but are presented without warranty, guarantee,or responsibility of any kind, expressed or implied. Statements or sug-gestions regarding possible use of our products are made without repre-sentation or warranty that any such use is free of patent infringement,and we are not recommending to infringe on any patent. The usershould not assume that all safety measures are indicated or that othermeasures may not be required.

Hylar 5000® is a registered trademark of Ausimont.

For information contact your AUSIMONT representative or:

Europe North AmericaAusimont S.p.A. (Italy) Ausimont USATel: +39-02-3835-1 Tel: +1-856-853-8119Fax: +39-02-3835-2129 Fax: +1-856-853-6405Email: [email protected] Email: [email protected]

An Introduction to PVDF CoatingsProduct Data Sheet

modified 11/6/01page 1 of 3 www.ausimont.com

F

PTFE

FC

F

FC

n1

H

PVDF

HC

F

FC

n2

Hylar 5000®

How PVDF Coatings are Applied:In most cases, the metal substrate will be aluminumor galvanized steel meeting high standards of unifor-mity and quality. In addition, the cleaning, preparationand chemical pretreatment of the metal must presentthe best possible surface for receiving the finishedsystem. Primers, for instance, impart adhesion andcorrosion resistance. A properly prepared metal, coat-ed with a HYLAR 5000 PVDF based system, assureslong-lasting beauty and protection.

Application is usually by coil coating or spray coating,and the coatings formulations are taylored to the

method of application. With either method, the coatedmethod then undergoes a baking process which coa-lesces the PVDF resin particles, fuses them together,and evaporates the solvent.

Proving the Long-Term Performance of PVDF:The primary objective to be achieved by using a PVDFfinish is, of course, the maintenance of originalappearance throughout long-term weathering.Accelerated testing, such as in an apparatus known asa weatherometer, can predict exposure of test panelsand confirm the expectation.







Florida Exposure 45˚ South of Commercially Made Panels*

CHA

LK R

ATIN

G

0

2

4

6

8

10

12

SILICONE POLYESTER

VINYL PLASTISOL

URETHANE

PVDF

AGING TIME (Years)0 2 4 6 8 10 12

0

2

4

6

8

10

12

CHA

LK R

ATIN

G

0

2

4

6

8

10

12

SILICONE POLYESTER

VINYL PLASTISOL

URETHANE

PVDF

AGING TIME (Years)0 2 4 6 8 10 12

0

2

4

6

8

10

12

*Data for various coatings may not reflect the complete range of grades available for each type coating

Hylar 5000®







For instance, after extended exposure to UV radiationand water cycles in a weatherometer, PVDF coatingsshow very little erosion of the protective film whencompared to other coatings systems.

Actual long-term exposure to weather affects theappearance of coatings in several ways - colorchange, gloss deterioration, and chalking( a form ofsurface erosion). All these changes can be measuredand in each case the results - based on 10 years ofexposure in southern Florida - demonstrate the supe-rior performance of PVDF (see graphs above).

Further examination of exposed test panels by elec-tron microscope confirms the lack of surface degrada-tion of PVDF coatings and the severe erosion sufferedby more conventional coatings systems.

PVDF in the Real World:As architects came to appreciate the benifits of PVDFcoatings such as those based on HYLAR 5000, moreand more projects around the world - monumental,industrial, commercial - have been specified withthese advanced coatings. Some of these structureshave been in place for more than two decades andtheir performance is compelling evidence that PVDF-based coatings retain their original beauty andappearance in real-world environments.

Florida Exposure 45˚ South of Commercially Made Panels*

*Data for various coatings may not reflect the complete range of grades available for each type coating

% G

LOSS

RET

ENTI

ON

(60˚

)

0

20

40

60

80

100

140

120 PVDF

AGING TIME (Years)0 2 4 6 8 10

SILICONE POLYESTERVINYL PLASTISOLURETHANE

Intro to PVDF Coating

Documents

Transcript of Intro to PVDF Coating