Polymer Library

Polyurethane Foams - January 2017

This month's topic focus is polyurethane foams.

The global polyurethane foam market is heading for continued growth over the next five years, according to recent research. The market is being driven by strong growth in the construction industry and rising demand for polyurethane building insulation, thanks to increased wealth, investment in infrastructure and industrial development around the world. The automotive sector is taking advantage of PU foams for seats and other parts of the car, and there is widespread use of flexible foams for upholstery, bedding and footwear. With the Polymer Library you can keep up to date with emerging technologies, processing methods and other factors driving the polyurethane foam market.

Why not review some of the items we've added to the Polymer Library about polyurethane foams?

Abstracts

These abstracts were highlighted in the January Newsletter and found in the Polymer Library.

Click on the 7-digit accession numbers to find out about ordering a copyright-cleared full text copy of the items shown.

1244881 - Factors that enable the formation of porous strut morphology in "Swiss Cheese" viscoelastic polyurethane foam technology
Several factors were investigated that affect porous strut morphology in the Highly Porous Supersoft Viscoelastic Foam. Porous strut morphology and high air permeability of the Swiss-Cheese TDI VE technology were found to be enabled by the combination of immiscible polyether polyols mixed with a third, highly hydrophobic polyol of high equivalent weight that is immiscible with either of the first two polyether polyols. Completely "punctured through" pores in struts were observed more frequently in foam samples where an isocyanate index of 90 versus 100 was employed. When isocyanate index is fixed to 90, it was found that a poly(1,2-butylene oxide) ("PBO") monol level of =>3.0 parts per hundred polyol (pphp) was needed to see the first signs of a "punctured" pore strut morphology. Studies show that a "high-Eq.Wt.-hydrophobic-polyol-leaving-voids" model is consistent with observed results. Hydrophobic polyols that allowed the formation of porous strut morphology included BO-4000 monol (Eq.Wt. ~ 4000) and PBD-10000 diol (Eq.Wt. ~ 5000). The use of these hydrophobic polyols also yielded air flows that were significantly higher than those obtained with the "standard" viscoelastic foam formulations that were prepared at the same isocyanate index. (22 ref)
Journal of Applied Polymer Science, Citation: 134, No.6, 2017, paper 4449, pp.19, DOI: 10.1002/app.44449
Aou K; Gamboa R R; Obi B E; Cook R; Latham D D

1246521 - Polyurethane market in the US (Open Access - Free PDF Available)
Expansion in the polyurethane resin market will be driven by healthy growth in construction spending, spurring demand for polyurethane building insulation, coatings, adhesives and sealants. Flexible and rigid polyurethane foams will remain the largest product segments, each accounting for more than 30 percent of all polyurethane demand in 2020. Sealants will present the best growth prospects for polyurethanes through the forecast period, supported by continued strength in the construction market and increased usage in automotive applications. Bedding segment revitalized by memory foam mattresses Moderating advances for flexible polyurethane will be spurred by continued strength in the household products market, where demand in the mature bedding segment has been revived by the success of viscoelastic (memory) foam. Further gains will be supported by carpet and flooring applications, where polyurethane is utilised as padding. Gains in this market will be boosted by growing expenditures in residential construction. Further gains will be constrained by maturity in key markets including furniture and textiles, both of which are subject to strong import competition. Rigid polyurethane holds growth in insulation applications Demand in insulation will be supported by updated regulations that require better and more effective usage of insulation, especially around ducts and the building envelope. Increased use per structure and upgrades of insulation for existing buildings will also aid rigid foam growth. Polyurethanes find use in many applications other polyurethane uses include adhesives, elastomers, coatings, sealants, and other applications such as binders and composites. Gains in coatings will be supported by demand from the construction market, where wood and concrete coatings will outperform other coating types. In addition, innovation in waterborne polyurethane dispersions will further stimulate demand in coatings as well as adhesives. Sealants growth will be fuelled by demand from construction applications such as joints, glass insulation, and air infiltration. This study analyses the US market for polyurethane. It presents historical demand data (2005, 2010 and 2015) plus forecasts (2020 and 2025) by raw material (polyols, diisocyanates, additives and other), product (flexible foam, rigid foam, coatings, adhesives and sealants, elastomers, other) and market (construction, household products, transportation equipment, packaging, other). The study also considers key market environment factors, assesses industry structure and evaluates company market share.
Citation: Cleveland, Oh., Freedonia Group Inc., 2016, 4pp, PDF 3463
Freedonia Group, Inc

1244797 - Electrical conductivity and EMI shielding effectiveness of polyurethane foam-conductive filler composites
The morphological, electrical, and thermal properties of polyurethane foam (PUF)/single conductive filler composites and PUF/hybrid conductive filler composites were investigated. For the PUF/single conductive filler composites, the PUF/nickel-coated carbon fibre (NCCF) composite showed higher electrical conductivity and electromagnetic interference shielding effectiveness (EMI SE) than did the PUF/multiwall carbon nanotube (MWCNT) and PUF/graphite composites; therefore, NCCF is the most effective filler among those tested in this study. For the PUF/hybrid conductive fillers PUF/NCCF (3.0 php)/MWCNT (3.0 php) composites, the values of electrical conductivity and EMI SE were determined to be 0.171 S/cm and 24.7 dB (decibel), respectively, which were the highest among the fillers investigated in this study. NCCF and MWCNT were the most effective primary and secondary fillers, and they had a synergistic effect on the electrical conductivity and EMI SE of the PUF/NCCF/MWCNT composites. From the results of thermal conductivity and cell size of the PUF/conductive filler composites, it is suggested that a reduction in cell size lowers the thermal conductivity of the PUF/conductive filler composites. (41 ref).
Journal of Applied Polymer Science, Citation: 134, No.5, 2017, paper 4373, pp.9, DOI: 10.1002/app.44373
Ji Mun Kim; Yeongbeom Lee; Myung Geun Jang; Chonghun Han; Woo Nyon Kim

1247144 - Cold plasma reticulation of shape memory embolic tissue scaffolds
Polyurethane shape memory polymer (SMP) foams are proposed for use as thrombogenic scaffolds to improve the treatment of vascular defects, such as cerebral aneurysms. However, gas blown SMP foams inherently have membranes between pores, which can limit their performance as embolic tissue scaffolds. Reticulation, or the removal of membranes between adjacent foam pores, is advantageous for improving device performance by increasing blood permeability and cellular infiltration. This work characterises the effects of cold gas plasma reticulation processes on bulk polyurethane SMP films and foams. Plasma-induced changes on material properties are characterised using scanning electron microscopy, uniaxial tensile testing, goniometry, and free strain recovery experiments. Device specific performance is characterised in terms of permeability, platelet attachment, and cell-material interactions. Overall, plasma reticulated SMP scaffolds show promise as embolic tissue scaffolds due to increased bulk permeability, retained thrombogenicity, and favourable cell-material interactions. (30 ref)
Macromolecular Rapid Communications, Citation: 37, No.23, 2016, p.1945-1951, DOI: 10.1002/marc.201600268
Nash L D; Docherty N C; Monroe M B B; Ezell K P; Carrow J K; Hasan S M; Gaharwar A K; Maitland D J

1246257 - Statistical evaluation of the effect of formulation on the properties of crude glycerolpolyurethane foams
In our pursuit of developing ecofriendly materials, the effect of the main components of the formulation used for the preparation of polyurethane foams (PUFs) derived from unrefined crude glycerol (CG) has been systematically studied. A series of PUFs has been prepared using formulations with judicious variations of the percentage of each component. The physical properties of the resulting PUFs were measured and the data collected were statically treated using a four-way functional ANOVA method. From the ANOVA results, the paramount importance that the blowing agent and the surfactant have on the regulation of density and thermal conductivity of PUFs was recognised. Regarding the mechanical properties, the isocyanate content presented a dominant influence on the increase of Young's modulus, toughness and compressive stress of PUFs. (29 ref)
Polymer Testing, Citation: 56, Dec. 2016, p.200-206, DOI: 10.1016/j.polymertesting.2016.10.006
Gama N V; Rui Silva; Costa M; Barros-Timmons A; Ferreira A

1246454 - A facile method to fabricate polyurethane based graphene foams/epoxy/carbon nanotubes composite for electro-active shape memory application
Shape memory polymers (SMPs) have attracted the attention of both the industry and academia due to the fact that they can deform and fix into a temporary shape, and recover their permanent, original shape upon exposure to an external stimulus. In this work we propose a novel, shape memory three-dimensional (3D) polyurethane-based (PU) graphene foam (PGF)/epoxy/carbon nanotubes (PGEC) composite. The composite uses epoxy resin (EP) as matrix, a low-density (about 0.030 g/cm^3), highly porous, commercially available PU sponges as the scaffold, and graphene and carbon nanotubes (CNTs) as conductive network. The proposed PGEC composites demonstrate excellent conductivity and could be triggered within 150 s by applying an electric field of approximately 1.43 V mm^-1. The proposed SMP composite material is simple and fast to manufacture, operational, and low cost. (47 ref)
Composites Part A: Applied Science and Manufacturing, Citation: 91, Dec. 2016, p.292-300, DOI: 10.1016/j.compositesa.2016.10.021
Jie Zhou; Hua Li; Weiwei Liu; Dugnani R; Ran Tian; Wenchao Xue; Yujie Chen; Yiping Guo; Huanan Duan; Hezhou Liu

1246197 - From rigid and flexible foams to elastomers via michael addition chemistry
Carbon-Michael chemistry can be used to produce rigid and viscoelastic foams, as well as flexible elastomers capable of effective function in traditional polyurethane applications. A simple synthetic procedure is provided for converting polyol oligomers and acetoacetate functionalised esters into useful building blocks. In this article detailed procedures for producing foams and elastomers by a carbon-Michael approach, the resulting mechanical properties of these polymeric materials, and structure property relationships for crosslink density are provided. These materials and techniques can potentially be substituted for isocyanate systems, especially in cases where isocyanates may not be advisable due to environmental, health, or safety concerns. (40 ref)
Polymer, Citation: 106, 5 Dec. 2016, p.128-139, DOI: 10.1016/j.polymer.2016.10.054
Sonnenschein M F; Werness J B; Patankar K A; Xin Jin; Larive M Z

DON'T FORGET!

The Polyurethane Foams Bulletin from the Polymer Library is currently available with a 20% discount for new subscribers. Sign up before 31/03/2017 at £208 for a whole year's subscription.

If you think that access to the Polymer Library might be of use, you can get in touch to find out more.



ALSO FROM SMITHERS RAPRA

Chemistry and Technology of Polyols for Polyurethanes, 2nd Edition, Two Volume Set
This comprehensive, two volume book considers the raw materials used to build the PU polymeric architecture. It covers the chemistry and technology of oligo-polyol fabrication, the characteristics of the various oligo-polyol families and the effects of the oligo-polyol structure on the properties of the resulting PU. Find out more...

Practical Guide to Flexible Polyurethane Foams
This book imparts a sound knowledge of flexible and viscoelastic polyurethane foam from its chemistry to calculations and formulating methodology for quality production. The author presents valuable detailed information on foam manufacturing, based on over 40 years' hands-on experience, at both local and international level. Find out more...

Recycling of Polyurethane Wastes
Recycling of polyurethane (PU) wastes is carried out to minimise waste and reduce environmental pollution. In this book, these methods are investigated to find a suitable process for waste reduction, protecting the environment, and preventing landfilling. Find out more...

%>