Upload
phamkien
View
233
Download
2
Embed Size (px)
Citation preview
www.fpinnovations.ca
Development of a Heat-
Resistant Polyurethane
Adhesive
Martin Feng
Jinlan Ju
Xiang-Ming Wang
Outline
Background
Objective
Methodology
Development of HRA polyurethane adhesives
Comparison between PUR and PRF in plywood
“burn through” test
Standard fire test of HRA PUR adhesive
Summary
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Engineered Wood Products (EWP): Beautiful Housing Materials
90% of Residential Housing in North
America
Engineered Wood Products
Background
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Engineering Wood Products in a Fire
Burn slowly
Char Retain 80% of strength
Degrade and soften Lose most of strength
Burn
EWP Burns and Collapses
Construction damages
Injury and/or death
Wood Adhesive
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Fire-Resistance Test of Finger-Jointed Wall Assemblies (2006)
American Wood Council (AWC) Canadian Wood Council (CWC)
USDA Forest Products Laboratory FPinnovations - Forintek Division
Type of Finger Jointed Lumber
(Douglas fir)
Assembly Fire-Resistance
Loading hour
Phenol-Resorcinol-Formaldehyde (PRF) 1 hour
Polyurethane (PUR) adhesive 51 min
Polyvinyl acetate (PVAc) adhesive 49min
Wall Assembly: U.S. 2006 International Building Code Table 720.1(2)
ASTM E119: Fire Tests of Building and Construction Materials
Background
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Background
Finger-Jointed Lumber used interchangeably
with solid sawn lumber if passing
1-hr Standard Fire Resistance rating
Western Wood Products Association (WWPA)
Glued Lumber Policy, 2007
(American Lumber Standard Committee)
Required: Heat Resistant Adhesive (HRA)
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Background
Applications of HRA Finger-Jointed Lumber
Market of Finger-Jointed Lumber in North America, 2007
•Separation in multi-story and multi-family buildings •Common walls in commercial structures •Mid-rised buildings (5,6 storey)
Voulme Value
Total stud lumber
consumption
8, 000
MMBF
C$ 1.9 billion
Finger jointed lumber 900 MMBF C$ 215 million
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Background
Commercial HRAs:
PRF & MF (formaldehyde based resin)
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Background
HRA
• Formaldehyde-free
• Colorless or light color
• Easy application
Market potential for
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
1-hr Fire Rating
ASTM E 119 : (Standard Test Methods for Fire Tests
of Building Construction and Materials)
ASTM D 7374: (Standard Practice for Evaluating
Elevated Temperature Performance of Adhesives
Used in End-Jointed Lumber)
Objective
To develop:
1C-HRA- polyurethane adhesive
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Requirements for HRA
1. Heat resistance Lose weight slowly
Does not soften at
elevated temperature
Maintain strength at high
temperatures under load
2. Flame retardancy Hinder ignition
Slow down fire growth
Produce substances as fire
barriers
Reduce heat of combustion
Form char layer
Objective
Mechanical properties
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
FPI’s patent publication # WO/2011/113137
pMDI + polyols polyurethane prepolymer
Formulation of PUR adhesives
PUR prepolymer + additives PUR adhesives
Methodology
Preparation of polyurethane adhesives
heating
Dry N2
Dry N2
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Methodology
Scaled Temperature Tension Test (STTT)
Thermal couple
Switch
sensor
220oC
Oven
Tensile
loading
10 MPa
Specimen
Scaled Temperature Tension Test FPinnovations-Forintek Division
Determination of Sample Failure point
Higher temp-to-failure means higher heat resistance.
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
Methodology
Scaled Temperature Tension Test (STTT)
Finger-Joint
ASTM D4688-99
Fabrication of Finger-Jointed Billets
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
HRA PUR Adhesives
Adhesive
name
Solvent or dispersion
media
Temperature-to-
failure (°C)
Time-to-failure
(s)
PUR-A NMP
(N-Methylpyrrolidone)
141.6 290
FR-PUR-A NMP 166 641
PUR-B water 36 34
PUR-C Solvent free 200 1635 (27min)
Heat-Resistance of commercial wood adhesives tested in 220 oC Oven
Note: Testing load was 1000 psi.
Heat-Resistance of commercial PUR adhesives
tested with STTT
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
HRA PUR Adhesives
Small Scale Tension Test of
the PUR Adhesives
220
0
50
100
150
200
250
0 500 1000 1500 2000 2500
time (s)
tem
pe
ratu
re (
oC
)
MA modified PUR
dark blue line
Control PUR
yellow line
MB modified PUR
sky blue line
best commercial PUR
FR-A
Purple line
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
HRA PUR Adhesives
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
HRA PUR Adhesives
SEM of Finger-Joint Glueline
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
PRF Glued 5-layer Plywood
At 2 min 21 sec At 1 min 29 sec
Polyurethane
Glued 5-layer Plywood
Comparison of flammability between HRA-PUR and PRF
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
At 6 min 28 sec
At 6 min 01 sec
PRF
Glued 5-layer Plywood
Polyurethane
Glued 5-layer Plywood
Comparison of flammability between HRA-PUR and PRF
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
At 13 min 40 sec At 10 min 21 sec At 15 min 25 sec
PRF
Glued 5-layer Plywood
Polyurethane
Glued 5-layer Plywood
Comparison of flammability between HRA-PUR and PRF
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
At 20 min 23 sec
At 20 min 10 sec
PRF
Glued 5-layer Plywood
Polyurethane
Glued 5-layer Plywood
Burned spot
Comparison of flammability between HRA-PUR and PRF
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
At 25 min 57 sec At 25 min 19 sec
PRF
Glued 5-layer Plywood
Polyurethane
Glued 5-layer Plywood
Comparison of flammability between HRA-PUR and PRF
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
At 27 min 59
sec At 35 min 17 sec
PRF
Glued 5-layer Plywood
Polyurethane
Glued 5-layer Plywood
Void
Comparison of flammability between HRA-PUR and PRF
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited.
PUR-Glued 5-layer Plywood
At 37 min 21 sec
PUR panel burned through
at 37min 21 sec. PUR
panel lasts 10 mins longer
than PRF panel
Comparison of flammability between HRA-PUR and PRF
Standard Fire Test on HRA PUR
Wall Assembly (ASTM D 7374-08 & D7470-08)
9 pieces of 2*4 finger jointed studs
2 plates
mineral wool insulation between studs
Gypsum board
Standard Fire Test on HRA-PUR
Fire Test Conditions (ASTM E 119)
•Expose wall assembly in
fire for 1 hr.
•Control furnace
temperature
•23,100 lbs constant load
on wall assembly
throughout testing
Time-Temperature Curve
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 29
ASTM E 119 Furnace (Front)
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 30
Construction of Wall Assembly
1 2 3 4
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 31
Construction of Wall Assembly
Stud attached with 5 thermal couples
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 32
Ignition of Furnace
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 33
Testing
Start testing Measure deflection of wall
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 34
Testing
In the beginning of test, mud
sealing was intact
After ~25 min., mud fell off and
flame shot out from drywall gap
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 35
Testing
At the very
moment that the
test passed 1-
hour fire rating,
where the wall
assembly was
still intact. The
test continued.
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 36
Wall Assembly was removed from the furnace
Drywall was
deformed and
cracked. FJ
lumber studs
were burning.
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 37
Completion of Testing
Studs were burned
more than 2/3 of original
width. Wood failed
under the stress load
(~450 psi). Wall
assembly bent towards
unexposed side.
FPInnovations’
polyurethane adhesive
reached 78 minutes
without failure
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 38
Burnt Finger-Jointed Studs
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 39
The Joints of the Burnt Studs
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 40
Cross Section of Burnt Joints
Depth Change of Burnt Joints
orig
ina
l
Note: The original depth of stud was 3.50 inches
The depth remaining ratio is 49+-6%, except specimens 1 and 9,
which were located on the sides of wall assembly
Specimen 1 2 3 4 5 6 7 8 9
average
remaining
Depth
(inches)
2.93 1.72 1.94 1.84 1.68 1.80 1.56 1.55 3.04
remaining
origingal
%
84 49 55 53 48 51 45 44 87
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 41
42
Tension test on burnt studs Finger Joint Clear Wood
Specimen Max Load Depth Width Stress Max Load Depth Width Stress
(pounds) (inches) (inches) (psi) (pounds) (inches) (inches) (psi)
1 12840 2.93 1.51 2896 52200 2.93 1.51 11775
2 9155 1.72 1.53 3479 18160 1.72 1.53 6901
3 7480 1.94 1.50 2574 20610 1.94 1.48 7198
4 9072 1.84 1.53 3216 22070 1.84 1.51 7949
5 7817 1.68 1.52 3055 19430 1.68 1.52 7594
average * 9273 3081 26494 7410
Specimen Max Load Depth Width Stress Max Load Depth Width Stress
(pounds) (inches) (inches) (psi) (pounds) (inches) (inches) (psi)
177 39450 3.50 1.50 7514 51560 3.50 1.50 9821
F97 28560 3.49 1.50 5451 35840 3.49 1.50 6840
average 34005 6483 43700 8331
Average * = average (2, 3, 4, 5). Stud 1 was located on the side, which was
burnt much less than the other studs and was not counted in calculations.
Remaining Strength
Finger Joints: 48% Clear Wood: 89%
@ 2013 FPInnovations. All rights reserved. Copying and redistribution prohibited. 43
Summary
Feasible to produce one component, room temperature curing
HRA polyurethane adhesives.
Unexpectedly, it was shown that flammability of HRA PUR was
less than that of PRF.
Studs burnt to only half of the original depth, which requires
wood adhesive highly heat/fire-resistant.
FPI’s polyurethane adhesive passed requirements of
HRA according to ASTM D7374 and ASTM E119 and
reached 78 minutes without failure, exceeding the 1-
hour target by a large margin.