Testing Furniture Composites for Flammability Using an Oxygen Index
Calorimeter, D. B. Parrish & S. A. Browning, Dow Chemical, Proceedings
of the Polyurethane Foam Association, May 13, 1993.
California, Illinois and Ohio have established the full scale TB-133
flammability test for public occupancy furniture under their jurisdictions.
This regulation is also under consideration by several other states. A
search was initiated for a small-scale flammability test which would permit
furniture manufacturers to pre-screen candidate cushion materials prior
to submitting their proposed products to the expense of full-scale testing.
The Oxygen Index Calorimeter (OIC), under development at the Dow Chemical
Co., as a predictive small-scale flammability test, is introduced in this
paper. It is presently intended as a low cost instrument for predicting
the flammability performance of upholstered cushions for use in public
occupancies. A description of the instrument calibration procedures for
obtaining heat release numbers, and data from a number of cushion composite
burns are provided. A number of full-scale mock-ups, burned at a single
TB-133 burn facility, provided a means for comparing results from an Oxygen
Index Calorimeter, The Cone Calorimeter, and the Ohio State University
(OSU) Heat of Release Apparatus.
Some Causes for Yellowing in Textile Materials, David M.
Hall, Auburn University, Proceedings of the Polyurethane Foam Association,
May 13, 1993.
The causes for yellowing in textile materials, specifically carpets and
upholstery fabrics, has been under investigation for years. Several potential
causes have been identified. The most common cause appears to be the inappropriate
use of optical brighteners (ultraviolet absorbers) in the cleaning agent
(shampoos etc.). Brighteners can give an optical illusion effect with
some colors, specifically gray or charcoal shades. In any case, the color
is often dulled by their use because they act to overdye the textile assembly
a blue shade. Other causes for yellowing include the use of chlorine bleaching
agents, the use of highly acidic or basic or anti microbial treatments,
among others. One of the best analytical methods to determine the causes
for discoloration in textiles is Energy Dispersive Analysis by X-Rays
(EDAX). Other methods include spectroscopic analysis after reproducing
the discoloration. Scanning Electron Microscopy (SEM) among others.
Models for Foam Formulating, Lee F. Lawler, Arco Chemical
Co., Proceedings of the Polyurethane Foam Association, May 13, 1993.
The properties of all water blown conventional polyether polyurethane
foams are controlled by formulation and processing conditions, more so
than individual component properties. For good quality, high air flow
cushioning grades, used for furniture bedding or carpet pad, catalyst
and surfactant effects are generally small. Therefore, only the major
effects of water, index, and polymer solids need be considered. The term
"polymer solids" is used interchangeably with "parts of polymer polyol"
even though these two items differ by a constant factor. Processing conditions
include those which impact foam breathability, structure and cell count.
The critical properties of foams are density and IFD. The general rule
of thumb is that as water increases (density decreases) IFD decreases.
This phenomenon is dependent on the amount of polymer polyol used and
the actual amount of water in the formulation, i.e. foam density. At densities
corresponding to between 2.5 and 4.0 php water, IFD increases with increasing
water. If more than about 30 Parts of high solids polymer polyol, like
Arcol® HS-100 is used, foam firmness always decreases with increasing
water.
This paper quantifies the effects associated with water, polymer polyol,
and isocyanate index through linear regression analysis of data generated
using designed experiments which serve to separate interactions between
direct variables. Density is modeled using its physical definition, density
= mass/volume. Use of such a definition as a modeling base could allow
more accurate extension to density ranges beyond the actual data range.
Unfortunately, such a simple mathematical definition does not exist for
IFD. However, accurate predictions of IFD are obtained using linear statistical
modeling techniques. It must be remembered, however, that purely empirical
models can only be confidently used over the specific data range from
which the model was developed. Also, since catalyst and surfactant concentrations
are not considered in the work, only quality "open" foams can reasonably
be predicted. Foams "artificially" hard, due to low breathability, will
not correlate with the models presented.
PURRC - A Flexible Polyurethane Foam Perspective, Andy
Kirk, ICI Poylurethanes, Proceedings of the Polyurethane Foam Association,
May 13, 1993.
Since the late 1980's, there has been a growing concern about the environment
in general, and about the efficient conservation of resources in specific.
Members of the Steering Committee of the Polyurethane Division of the
SPI became concerned about the industry's customers' perceptions that
polyurethanes, as thermosets, were non-recyclable. Polyurethane foam customers
compared polyurethanes to thermoplastics and perceived that they were
not recyclable since they could not be melted and reprocessed once molded.
In 1990, the Steering Committee formed the PolyUrethanes Recycling and
Recovery Council (PURRC). The goal set for the PURRC was to reduce significantly
the amount of polyurethanes being disposed to landfills. Among PURRC's
objectives was 1) to establish parity when compared with alternative materials
for which recycling was not perceived to be a problem; 2) recycle polyurethanes
to remove the perceptions that they could not be recycled; and 3) create
the environmental responsibility of polyurethanes as a positive design
issue.
This paper discusses several processes for recycling, recovery and reuse
of polyurethane foam. Among them are opportunities for removing and recovering
and reusing flexible polyurethane foam from automobile seats and mattresses,
adding reground flexible foam scrap to slab foam, chemical recycling and
energy recovery.
Emissions and Emission Control for Flexible Polyurethane Foam,
Bert Veenendaal, RAPPA Inc., Proceedings of the Polyurethane Foam Association,
May 13, 1993.
This paper provides an assessment of the emissions generated during the
manufacture of flexible polyurethane foam, the current status of control
technologies, and recommendations for controlling these emissions.
The True Cost of Meeting California TB-133, H. Talley,
The Hugh Talley Co., Proceedings of the Polyurethane Foam Association,
September 30, 1993.
The costing of furniture products is a difficult task because of the
style/fashion requirements and the need to remain competitive. Costs and
cost ramifications are some of the least understood subjects in all areas
of upholstered furniture. Both industry people and non-industry people
have tried to use a simple percentage increase number to represent the
cost increase of making all furniture, which passes TB-133. When using
this approach, it must be remembered that the percentages must be accompanied
by a great deal more information in order to be meaningful and useful.
Examples are provided in this paper demonstrating the cost increases
associated with making stacking chairs and sofas which pass the TB-133
Flammability Test. Information is presented on the effects of using different
manufacturing possibilities such as types of barriers, fabrics, flame
retardant foam, back coatings and other ways to meet TB-133, on the final
cost of the furniture.
New Ultrasoft Low Density Foams as Alternatives to Fiber Batting,
S. L. Hager and R. D. Duffy, Arco Chemical Co., Proceedings of the Polyurethane
Foam Association, September 30, 1993.
Polyurethane foam and polyester batting are cushioning materials that
have found widespread use in a variety of applications. In some cases
they compete for the same market, in others they are used together in
a complementary fashion, while in still others one or the other is dominant
for performance or cost reasons. Foam has tended to be the dominant material
in those applications requiring higher load bearing and/or long term durability
such as cushion cores, carpet pad and mattress toppers. Fiber batting
has intended to dominate lighter duty applications requiring high filling
efficiency or a very soft surface such as comforters, toys, loose backs
and cushion wraps.
A new foam formulating technology is introduced in this paper, Softcel™
foam, that allows the production of ultrasoft low density polyurethane
foam having cushioning characteristics closer to that of fiber while maintaining
the durability and other performance characteristics of foam. This new
foam is a major extension of the Ultracel® slabstock technology. A variety
of slabstock grades have been produced on either full scale or pilot scale
machines. The full grade range possible with this technology using auxiliary
blowing agents is expected to run from below 1.0 pcf to 1.8 pcf with IFDs
ranging from about 5 to 20. Auxiliary blowing agent requirements to soften
the foam are substantially less than for conventional foam and can be
totally avoided in many grades. The limited data available at this time
indicates that these foams perform well in small scale ignition and smolder
resistance tests such as CAL TB117 and the UFAC Barrier Test. Comforters
produced with low density soft foam grades have exhibited feel and drape
comparable to fiberfil but with improved durability.
Texaco Chemical Company, Propylene Oxide Business Entry,
J. Lemonds, Texaco Chemical, Proceedings of the Polyurethane Foam Association,
September 30, 1993.
This paper introduces Texaco Chemical Company's entry into the propylene
oxide business with a new world class facility presently being constructed
at their flagship Neches Chemical Plant in Jefferson County, Texas. Propylene
oxide is the building block chemical from which polyether polyols are
made.
Propylene oxide design capacity is 400 million pounds per year. Coproduct
MTBE is 1.3 billion pounds, or 15,000 barrels per day in motor gasoline
terms. Total capitol for this project, including working capital, exceeds
five hundred million dollars. Mechanical completion is expected in the
third quarter of 1994.
This presentation discusses FR compliance misconceptions dealing with
issues such as how FR additives affect furniture cost, lead time for furniture
production, furniture durability, and product warranties. A case is made
for Calif. TB 133 compliance.
Various research strategies to determine code compliance are provided.
Techniques for creating Calif. TB 113 compliant furnishings are also explained.
California Technical Bulletin 117 Revisited, S. E. Wujcik,
T. M. Smiencinski, R. F. Pask, BASF Corporation, Proceedings of the Polyurethane
Foam Association, September 30, 1993.
During the past 20 years, more than 30 flame tests have been developed.
These range from a simple measure of the amount of oxygen needed to support
combustion to full scale furniture burns under controlled conditions.
The California TB 117 flame test, by far, is the most frequently run standard
furniture flame test. It has been around for more than ten years.
The requirements for passing TB 117 are fairly easy to meet. The addition
of a small amount of a chemical, usually a halogenated phosphate flame
retardant metered in during foaming, is all that is required. Most of
these chemicals have little effect on the foam process or the foam grades
produced. More recent flame tests, such as BS-5852, Part II, Crib 5 or
CAL TB 133 are much more involved. In order to pass these tests it is
necessary to make significant changes in equipment and the chemical formulas.
This paper describes the scope of the California TB 117 flame test along
with a procedure for Resilient Cellular Materials and formulations for
producing flexible polyurethane foams.
Predictions of TDI Emissions from Flexible Foam Production Line,
H. Metcalf, F. Sweet, Dow Chemical USA, Proceedings of the Polyurethane
Foam Association, September 30, 1993.
Governmental regulation (federal, state, and local) of industrial emissions
is expected to increase over the next few years. Regulations relating
to the control of or tax on emissions of TDI from flexible slabstock polyurethane
foam production lines, are possible. As a result, it has become increasingly
attractive, if not necessary, to develop a method for predicting TDI emissions
from the exhaust stacks for such facilities. Data from seven full-scale
production facility emission surveys were entered into a database and
analyzed per statistical method techniques.
The data included information on foam grade and formulation, component
flow rates, run times, ambient conditions, and TDI emission levels. The
2,4- and 2,6- TDI emissions were measured from the pour line exhaust stacks
by The Dow Chemical Company Health and Environmental Sciences personnel,
utilizing EPA recognized methods.Two preliminary mathematical models have
been developed to calculate the expected TDI emissions based on foam formulation,
plant and ambient condition information. The resulting models allow a
foam production facility to predict the total 2,4- and 2,6- TDI emissions
from a given set of foam formulations using ambient condition information
for the day on which the foam is produced.
The use of Unilink 4200 in Flexible Polyester-Based Polyurethane
Foams, D. W. House, R. V. Scott, Jr., United Oil Products, Proceedings
of the Polyurethane Foam Association, September 30, 1993.
Unilink® 4200, 4,4-bis-(secbutylamino) diphenylmethane, is a proprietary
UOP additive that reacts in a urethane foam formulation to increase both
the level of urea groups present and the hard segment content. As an aromatic
secondary diamine, it reacts with the polyisocyanates to produce linear
polymer chains. Although primary amines are known to react too rapidly
for use in flexible foam formulations, the liquid Unilink 4200 has a reaction
profile more similar to the polyol/isocyanate reaction.
Polyester-based urethane foams are typically chosen over polyether-based
foams in applications requiring greater load-bearing, higher tensile strengths,
and higher elongation. The use of Unilink 4200 in typical polyester-based
formulations has led to even grater increases in these three important
areas without increasing foam density. In general, the use of Unilink
4200 led to increases in load bearing of about 30% at 25% deflection and
40% at 65% deflection. Tensile strengths (both perpendicular and parallel
to foam rise) increased significantly with Unilink 4200, and this increase
was greater at higher densities. Elongation was only slightly improved
at lower density; however, at 3.2 pcf (51kg/m(3)), the elongation was
45% greater perpendicular to foam rise and 58% greater parallel to foam
rise.
Typically, efforts to increase tear strength in foams have usually been
at the expense of other properties such as elongation. The use of 5 php
of Unilink 4200 led to an average increase of over 40% throughout the
entire density range studied, and did so without adversely affecting elongation.
Though air flow was lower when Unilink 4200 was added to the formulation,
there was no shrinkage of the uncrushed foam. All of these benefits have
been obtained without increasing foam density above that of the control
foams (without Unilink 4200).
In the present work, polyester foams representing densities ranging from
1.6 to 3.4 pcf (28 to 54 kg/m(3)) were studied as a function of density,
blowing catalyst, surfactant, and Unilink 4200.
Auxiliary Blowing Agent Substitution in Slabstock Foams,
C. Fiorentini, Cannon Group, T. Griffiths, TG Cellsoft Ltd., M. Taverna,
Cannon Group, B. Collins, Cannon USA, Proceedings of the Polyurethane
Foam Association, September 30, 1993.
As the pressure to eliminate chlorinated products such as Chlorofluorocarbons,
methylene chloride, 1,1,1,-trichloroethane etc. (CFC's) from the environment
increases worldwide, it is becoming necessary to eliminate them from polyurethane
foam production. These additives have already been banned in some countries.
The impact on the flexible foam industry would be to increase foam prices
and to eliminate certain soft grades.
The use of liquid carbon dioxide (CO-2) as an auxiliary blowing agent
in a polyurethane foam is a good and well accepted idea. Handling this
liquid, which is a gas at room temperature, has always been one of its
main problems.
Cannon has developed a new process for manufacturing flexible slabstock
foams without the use of CFC's. This revolutionary new process called
CarDio® (from carbon dioxide), has been able to completely eliminate the
use of CFC's and other volatile Organic compounds (VOC's) from flexible
foam slabstock production. This has been done without sacrificing the
foam's physical mechanical properties. The CarDio process also dramatically
reduces the size requirements for foaming plants, thereby allowing all
the advantages derived from a reduced floor space and plant volume. Flexible
slabstock foamers are able to continue producing their existing foam grades
at a lower chemical cost due to the significant price differential between
CFCs, ABAs, and carbon dioxide. Patents have been applied for the process
The Rapid Cure Process-Industrial Experience, Engineering and Formulation
Principles, H. Stone, E. Reinink, S. Lichvar, W. Carlson, C. Sikorsky,
General Foam, Proceedings of the Polyurethane Foam Association, September
30, 1993.
The concept of rapidly cooling freshly prepared flexible polyurethane
foam in order to reduce space requirements and storage time in the plant
has been recognized for a long time. Recently, growing concern about ozone
depletion in the upper atmosphere, has led to a phase-out of chlorofluorocarbon
blowing agents, and has placed new emphasis on developing alternative
approaches for producing flexible slabstock foams.
The objective of the work, presented in this paper, is the development
of a foaming process using only water as the source of gas for foam blowing.
This approach presents two major problems. The first is the engineering
problem of avoiding long exposures to the high temperatures encountered
in using only water as the blowing agent, particularly for low density
foams. The second is the problem of maintaining physical properties and
performance for the full range of density and hardness grades of foam
in industrial use.
The Rapid Cure Process basically consists of a series of cooling chambers
over which the foam passes after completing its rise. At that time the
hot gases as well as small amounts of volatile impurities are removed,
and the foam is cooled to a safe temperature. The preferred cooling medium
is air being drawn through the foam. The exhaust gases are treated in
a carbon bed to remove trace impurities, including TDI, before they are
discharged to the air.
One of the additional benefits of this process is a significant improvement
in foam uniformity, particularly in uniformity of IFD throughout the foam
block. Another is a general improvement in the plant atmosphere by elimination
of trace contaminants in the air.
This paper describes equipment modifications for the full-scale foam
production, and formulation developments, to optimize physical properties
and processing, in the laboratory, pilot plant and on full-scale production
runs.
After more than a year of commercial production experience with the Rapid
Cure Process, General Foam has the ability to handle a variety of foam
grades with little or no changes in physical properties from their previous
standards. Engineering changes have also been introduced in the process
to optimize performance.
Variable Pressure Foaming - A New Generation Foaming Technology,
R. Triolo, Foamex, Proceedings of the Polyurethane Foam Association, September
30, 1993.
A new commercial process for foaming under variable pressure has been
developed. The process offers numerous advantages, the first of which
is that no auxiliary blowing agents are necessary to produce lower density
foams. The formulation advantages now make density virtually independent
of water concentration and auxiliary blowing agents. Foams can also be
produced with high load bearing without the use of polymer polyols.
Commercial experience with the system has demonstrated that the foams
exhibit superior physical properties. The resulting foam is more open,
has better resilience, superior compression set, and better mechanical
properties. There is also greater control over the density and hardness
variation from run to run. The process is fully automated, offering superior
control over the final product. The environmental advantages of the new
system are that no auxiliary blowing agents are used, the reaction gases
are treated before exhaust, and there are no isocyanate vapors in the
production area.
All contents copyright © 2000 Polyurethane Foam Association,
Inc.