Polyurethane Construction Adhesives

for Flooring Installation

Workshop on TDI/MDI for EPA Staff

February 15, 2012

Michael Chronister

Chief Technology Director

Bostik Americas

This presentation represents the views of Bostik, Inc. only. It does not represent the views of the 

American Chemistry Council Center for the Polyurethanes Industry, or the Adhesive and Sealant Council. 

ASC, ACC and CPI shall have absolutely no liability, under any theory of liability, in connection with 

resulting from the use or misuse or, reliance upon, this presentation or the information in it.” 
Company Background

• Bostik is one of the top 5 adhesive companies globally

• 2010 sales of $1.9 billion

• Founded in 1889 as the Boston Blacking Company

• Present in around 40 countries
Business Portfolio

• Bostik’s Business is split between 55% in Industrial markets and 45% in 

Construction markets

• The Consumer business is part of our construction portfolio

• In Consumer markets

– More than 2,000 products sold in over 120 countries across the world guarantee 

the success of Bostik’s products on the consumer market

– Every day, they meet needs in home improvement, stationary, repair, assembly, 

decoration, weatherproofing... 

– These products are readily available in retail outlets, hypermarkets and 

specialized distribution
US Portfolio

• Total Bostik US revenue in 2011 – $500 M

• Consumer & Construction Business Unit revenue in 

2011- $100 M

• Consumer portfolio focused on

– Hardwood Flooring Adhesives

– Tile and Stone Installation

– Wood Working Lubricants
Construction Adhesives -

Flooring

• Bostik introduced moisture curable PU flooring adhesives 

in the late 1980’s

– Ultraset® Hardwood Adhesive was the first flooring adhesive 

capable of bonding solid hardwood flooring

– Specialty applications only – solid wood / high moisture 

environments

• Hardwood adhesive market dramatically

changed in 1994 with the shift away from

rubber-based chlorinated solvent technology

– Montreal Protocol – in force 1989
Construction Adhesives -

Flooring

• Bostik introduced Bostik’s Best in 1994 – high solids moisture 

curable PU 

• Since then, Bostik alone has sold over 

300 M pounds of adhesive – mainly in 

commercial/professional markets

• Competitors also participate
• Why glue down hardwood flooring with PU 

adhesives?

– On-slab, on-grade prevalent in many US geographies 

• Mechanical nail down is not an option

– Outstanding adhesion to both cement substrate and 

hardwood flooring

• Mechanical fastening to concrete is not advantageous

– High elongation, ultimate strength, and overall 

toughness to accommodate movement in wood caused 

by humidity and temperature

Construction Adhesives -

Flooring
• Why glue down hardwood flooring with PU 

adhesives?

– Water-borne technology has compatibility issues with 

wood

• Causes undesirable and unattractive swelling hardwood flooring

– Outstanding moisture vapor transmission reduction 

capabilities 

• Reduces number cause of floor failures

– Ability to serve as an adhesive, moisture vapor retarder, 

sound deadening, and crack isolation in one product

Construction Adhesives -

Flooring
Application

• Hardwood flooring adhesives are liquid products 

at room temperature and trowel applied

• Used to bond solid hardwood and engineered 

wood (multiply wood with decorative wood 

finish) to floor substrate (typically concrete)

• First step is to apply the adhesive to the 

subfloor substrate
Installation

• After adhesive is applied, the installer places 

the hardwood flooring into the adhesive

• The installer works on the floor setting the 

wood into place to cover the subfloor

• After floor is installed, adhesive reacts with 

atmospheric moisture or moisture in wood 

flooring and/or substrate to cure to a 

thermoset, elastomeric material to hold wood 

into place.
Hardwood Flooring

• Examples of hardwood 

flooring applications –

most living spaces in a 

household

• Provides warm, appealing, 

and inviting wear surface

• Wood flooring is a natural, 

sustainable building 

product
Adhesive Details

• Hardwood flooring adhesives are single component, high solids, room 

temperature applied materials

– Can be 100% solids and zero VOC

• Liquid, urethane prepolymer content of the adhesives are around 15-

20% of the adhesive composition

– Remaining ingredients include liquid and solid extenders along with other 

minor ingredients 

• Prepolymers are mid-molecular weight (2500-5000 g/mol) material 

based on polyether polyols reacted with MDI or polymeric MDI
Adhesive Details

• Unreacted %NCO of the prepolymers are low – 2-4% 

NCO by weight

• Free monomeric MDI range from 0.1 to 1.0% of the 

finished compounded formulation

• Full cure occurs from moisture reacting with all of the 

unreacted NCO functionality to form urea crosslinks 

creating a permanent, thermoset polymer network
Label Details

• All Bostik pails carry this statement 

• Front Panel Label

– Warning: Inhaling vapors harmful. May cause allergic skin 

reaction. Skin, eye, and throat irritant. Harmful if swallowed. 

See additional cautions on back panel.
Label Details

• Back Panel Statements

– Warning: This product is irritating to the eyes and skin. Causes 

respiratory tract irritation and may cause allergic skin reaction

– Precaution: Wash hands after handling and before eating. Use 

with adequate ventilation. Wear appropriate protective 

equipment to avoid contact with skin and eyes.
Label Details

• Back Panel Statements

– First Aid: Immediately flush eyes with plenty of water for at least 15 

minutes. Get medical attention or advice. For skin contact, flush with 

large amounts of water while removing contaminated clothing. If skin 

irritation persists, call a physician. If inhaled, immediately remove the 

affected person to fresh air. Call a physician if symptoms develop or 

persist. If ingested, get immediate medical attention.

• Found on the ingredient list

– Methylene diphenyl isocyanate (MDI) (101-68-8)
Consumer Details

Bostik Labels

Two consumer websites:

www.bostikdiy.com

www.bostikdiytube.com
Thank you for your time and attention.

Questions? 

Contact Information:

Michael Chronister

Chief Technology Director

Bostik, Inc

701 Veterans Circle

Warminster, PA 18974

215-442-6001 (w)

215-779-9440 (m)

michael.chronister@bostik-us.com