INTUMESCENT

that Supports UsProtecting the Steel

BINDERS

Emultex: the benchmark for intumescent bindersDespite its inability to burn, steelwork e.g. in high rises may bend and collapse at temperatures above 500°CIntumescent coatings shield the steelwork with a protective layer of foam and char formed above 200°CSynthomer binders enable the crucial first step with a stable matrix for the protective foam to build uponStarting formulations and polymers available in a wide variety

Fire test on 6mm steel plates with Emultex FR 728

Emultex FR 728

A thin coating may save your lifeAn area of glowing importanceThe majority of multi-storied high-rises today have a steel skeleton. Load-bearing steel structures are a key concern for building authorities.

AlthoughAlthough steel does not burn, it is has to be protected against fire. When structural steelwork reaches a critical temperature, it can lose its load bearing capability and buckle or collapse, with drastic consequences for the stability of the building it is supporting. Without proper protection of the steelwork it may bend and collapse within minutes at temperatures above 500°C.

ThusThus the extra time provided by intumescent coatings (means a ‘swelling up’ or ‘expansion’ - one which expands when in contact with heat) slows and even potentially prevents this destruction process.

In the past a protection time of 30 – 60 minutes was seen as sufficient, but new standards increasingly require 90 – 120 minutes, which require highly specialised binders.

Intumescent products are available as paints and coatings which are applied to protect a whole variety of materials, including steel structures, metal sheets, wood, plaster and concrete. In this brochure only coatings for steel structures are described.

Finding the fireproof formulaA mechanism that saves livesTheThe intumescent reaction is activated by heat at approximately 200°C. It is an endothermic reaction that absorbs heat, emits inert gases and creates an effective insulation layer. Depending on the composition, such an intumescent coating will swell up 10 to 100 times in thickness to build a foam char barrier that insulates the underlying material.

ThisThis intumescent process may be divided into different steps, dependant on the specialist raw materials used:

1. At temperature of 250°C the thermoplastic binder (e. g. EMULTEX FR 728) melts to form a soft matrix in which further thermochemical reactions can take place.2. Ammonium polyphosphate (acid donor), which is the major ingredient of the intumescent coating, decomposes generating polyphosphoric acid. decomposes generating polyphosphoric acid.3. This polyphosphoric acid reacts with a carbon donor (usually pentaerythrol or dipentaerythrol) to form an inorganic/organic ester.4. A blowing agent (e.g. melamine) decomposes and releases gases allowing the molten resin and ester to create a foam that forms an insulating barrier which adhe adheres to the steel.5. When the temperature keeps rising, the ester decomposes to form a tough carbon char.

The resulting char insulates the substrates against heat. Thus, the protection time for the steel structure depends on the quality (density, adhesion) and thickness of the char.

The right choice of the binder in such an intumescent coating is crucial because only special binders are effective in forming a stable matrix, which results in a stable foam and char.

Some other functional raw materials may be used to improve the performance:

• TiO2 is used as pigment and as catalyst for the char fo formation. Thus the choice of the right TiO2 is essential. • Flame retardants may be used in order to reduce spread of flame rate and give self-extinguishing properties to the coating. (Emultex 5535 already contains a flame retardant.) In addition Melamine, used as blowing agent, is a nitrogen based flame retardant which can show e excellent flame retardant properties.

• In combination with phosphorous synergists, melamine can further increase char stability through formation with nitrogen-phosphorous substances. Melamine can act as blowing agent for the char, enhancing the heat barrier functionality of the char layer.

• Addition of Lapinus fibres may improve drying properties of the paint (e. g. less mud cracking, higher low shear viscosity), also improve stability of the char. During the violent conditions of a fire, a fibre reinforced char will last for a longer period of time and increase the performance of the intumescent coating.

Example:steel beam and column covered with intumescent paint

Our portfolio for intumescent coatings

Product Solid Content [%]1 pH value2 Viscosity [mPa*s]3 Tg [°C] MFFT [°C]

Emultex FR 728

Emultex FR 797Notes: 1According to ISO 3251 2According to ISO 976 3According to ISO 2555 (Brookfield) *Data describe typical properties - not product specifications

50.0

47.0

4.0

4.5

2200

1100

23

13

13

2

Emulsion properties*

Emultex binders for intumescent coatings

Product

Emultex FR 728

Emultex FR 797

Benefits Recommended use

APEO-free alternative to Emultex 523

Slow developing compact foam, good water resistance

Rapid foam generation, up to 60 min coatings

For protection time up to 120 min

Our starting formulation

Solid Content [%] PVC [%]

63.9 80.0

Test data

1

2

3

4

5

6

77

Starting formulation based on Emultex FR 728

Ingredients

Emultex FR 728 (50 %)

Water

Reofos 50

Exolit AP 422

Charmor PM 15

Tioxide TR81

MelafineMelafine

Instruction: Add in order and mix. Keep temperature below @ 40°C.

Instruction: Mix until dispersed, maintaining temperature below @ 40°C.

Supplier

Synthomer

Whitchem

Clariant

Perstorp

Huntsman

OCI Nitrogen

Role

binder

plasticiser

phosphate source

carbon source

pigment

blowing agent

14.30

28.99

0.85

25.32

9.18

12.28

9.089.08

100.0

pbw

America, Europe and South East Asia. In March 2017, we acquired the coalescing agents and Butyl Ethyl Propanediol (BEPD) business from Perstorp Oxo Belgium AB. The newly acquired businesses significantly improve our footprint to a number of speciality markets which we will continue to serve through a strong network of local technical service and sales branches, supported by regional application dedevelopment and production in our key markets. We deliver the right formula, globally, individually.

Synthomer is one of the world’s leading suppliers of emulsion and speciality polymers supporting leadership positions in many market segments including coatings, construction, technical textiles, adhesives, paper and synthetic latex gloves. The company has its Head Office in London (UK) and provides customer focused services from operational centres in Harlow (UK), Marl (Germany), Kuala LumpurLumpur (Malaysia), Shanghai (China) and Dubai (UAE). In June 2016 we have acquired the Monomers, Dispersions and Powders business (MDP) from Hexion with dedicated production sales and customer service facilities in North

Disclaimer: This information and any other advice or recommendations given or made by us (collectively “Information”), are provided in good faith and are not intended to, nor do they, constitute professional advice or services. Information is provided “AS IS” and on an “AS AVAILABLE” basis and without warranty. We do not warrant or accept responsibility for the accuracy, timeliness or completeness of the Information, or for the suitability of the Information for a particular purpose. We do not accept responsibility, and exclude all liability (including(including under any implied warranties), for any matters arising out of or in connection with your reliance on the Information (including as to infringement of third party intellectual property rights) to the fullest extent permitted by law. Any Information concerning any possible use or application of Synthomer products is given by us in good faith; we do not warrant the fitness of any Synthomer products for any particular purpose and it is entirely for you to satisfy yourself fully as to the suitability of Synthomer products for any particular purpose. purpose. Synthomer products are sold in accordance with Synthomer’s standard terms and conditions of sale which are available from www.synthomer.com/tc.

Group Head OfficeSynthomer plc45 Pall MallLondon SW1Y 5JGUnited Kingdom

info@synthomer.com

Operational Centre EuropeSynthomer Deutschland GmbHWerrastraße 1045768 MarlGermany

europe.coatings@synthomer.com

www.synthomer.com

Leading in emulsionsand speciality polymers