Heat Stable Adhesives

Loctite Aerospace 2850 Willow Pass Road P.O. Box 312 Bay PoinL CA 94565-0031, 

Abenbury Way, Wrexham Industrial Estate, Wrexham LL 13 9uz, Wales, 

Note Eor the Electronic heat-stahle adhesives our readers may also refer to the list of suppliers published in Volume I of the Handbook. 

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Plate 21 EUROFIGHTER Typhoon. Modem fighter aircraft need heat stable adhesives for the bonding of some parts that become very hot dnring flight and combat. 

After reading some chapters on the various industries, the reader will need specific and detailed technical characteristics concerning the adhesives or sealants that they may consider for their own applications/end uses. For instance, those who wish to bond metal parts, those working in aircraft construction, automotive, and transportation, should read the chapters Epoxy adhesives , Engineering adhesives , and maybe also Heat stable adhesives . 

Chapter 4 UV curing, hy Christian Decker, Mulhouse University, France Chapter 5 Heat stable adhesives, hy Guy Rabilloud... 

Editor s note In Volume 2 of this Handbook, our readers will find a very important and comprehensive chapter titled Heat Stable Adhesives by Guy Rabilloud, which provides much new information of such adhesives that may resist up to 300 or 400 C, for instance for aerospace, mechanics, machines or appliances. 

A very large study of heat stable adhesive is provided in Volume 2 in the chapter Heat stable adhesives by Guy Rabilloud. 

Detailed information on heat resistant adhesives (bismaleimide, cyanate esters, etc.) is available in the chapter Heat stable adhesives in Volume 2. 

A discussion of heat-stable adhesives is provided in Chapter 9 (by Guy Rabilloud) of this book. 

With its mirror finish, aluminized clothing is very effective at reflecting radiant heat. The aluminized coating can reflect up to 95 percent of thermal radiation away from the wearer, and some fabrics can withstand temperatures as high as 3000°F for short durations. Aluminized fabrics are often constructed with a flame-resistant base fabric and multiple layers of aluminum, protective films, and heat-stable adhesives so that when one layer of aluminum breaks down, another layer is there to protect. This multi-layer structure improves abrasion resistance and helps ensure that fabrics remain highly reflective even after repeated use and proper care and cleaning. 

The polymerization in method [III] will probably be unsuitable for industrial production due to the heat of polymerization, but it can be used to produce a freeze-thaw stable adhesive with rapid drying and good adhesion to paper, which cannot be obtain by other polymerization methods. However, the water resistance of the latex film is not improved. 

Yersinia enterocolitica Proliferation in gut associated lymphoid tissue (facultative intracellular pathogen)(heat stable enterotoxin, LPS, invasin, attachment/invasion protein adhesion Ail) Bacillus cereus Emetic toxin (vomiting) Enterotoxins (diarrheal illness) ... 

Lipopolysaccharides are heat-stable complex amphiphilic macromolecules indispensable for the bacterial growth, viability and for the correct assembly of the external membrane they represent a defensive barrier which helps bacteria to resist to antimicrobial compounds and environmental stresses and are involved in many aspects of host-bacterium interactions as recognition, adhesion, colonization, and, in the case of extremophile bacteria, in the survival under harsh conditions (Alexander and Rietschel, 2001 Raetz and Whitfield, 2002 Raetz et al 2007). LPS are also called endotoxins because they are cell-bound and, once released, play a key role in the pathogenesis of Gram-negative infections, in mechanisms as... 

Since in the final state these are thermoplastic adhesives, the utilization temper-atiue of the adhesive bonds is Umited to approx. 80°C. Some adhesive types are heat-stable up to 130°C, although the adhesive strength at this temperature is greatly reduced since in this case the inherent strength of the cyanaciylate determines the stability of the plastic bond. 

Anaerobic adhesives are heat-stable up to about 200°C and show no loss of strength under a continuous heat load of up to 130 C. The temperature range for use of these adhesives is therefore above that of most other plastics. 

A certain percentage of resin is almost always incorporated into formulations, with resin content varying from 8 to 25%. Hydrocarbon resins are used most often, but rosin esters, terpenes, and indene resins, which are more heat stable, are also common. Resins provide better flow, hot-tack, adhesion, and wetting characteristics. 

Chem. Descrip. Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate CAS 52829-07-9 EINECS/ELINCS 258-207-9 Uses Lt. stabilizer in polypropylene, HDPE, ABS, PU, PS, polyester, polyamide, coatings, adhesives, and rubbers Features Heat-stable... 

Uses Antimicrobial, preservative, stabilizer, slimicide for use in latexes, emulsion paint, aq. slurries, adhesives, tape Joint compds., o/w emulsions, paper coatings, pesticides, water-based inks, hides and skins USDA approved for paints used in federally inspected plants and packing adhesives having min. contact with meat or poultry food prods. food pkg. adhesives, paper food-contact slimicide Features Inhibitor of bacteria, yeast, and fungi heat-stable, low corrosivity no formaldehyde released... 

While condensation polyimides afford the most heat stable polymers, they are generally difficult and expensive to process and afford voidy parts. Epitomical of the heat resistance properties of condensation polyimides are the 20,000-l- and 9,000 hour service lives of NOLIHID A380 adhesive for titanium bonds at ten eratures of 500<> and 575°F, respectively. 

Bitumens are stored at 120-200°C and at these temperatures amine groups in the adhesion promoters can react with acid groups in the bitumen to form less active amido compounds, or can degrade by oxidation. The rate of degradation depends on the acid value of the bitumen and the chemistry of the adhesion promoter. Where possible, the adhesion promoters should be added to the bitumen just before use. So-called heat-stable products based on less reactive tertiary amines or polyamines have been developed for situations where the treated bitumen must be stored for longer than a few hours. Field studies have shown that treatment of bitumens with adhesion promoters improves the performance of roadways. 

There are several reasons why cyanoacrylates are attractive as adhesives. They are easy to apply, one-part, 100% reactive, storage-stable adhesives. They cure rapidly at room temperature when spread in thin films between substrate surfaces, and they form strong bonds between a variety of substrates. However, cyanoacrylates do have several serious shortcomings including poor heat resistance, poor moisture resistance, poor peel and impact resistance, and limited ability to fill gaps and to bond porous substrates. The poor durability and impact resistance have been particular limitations in metal-to-metal bonding. 

Hot-melt-type (thermoplastic) polyimide films have been developed as high-heat-resistant adhesive materials. Mitsui Chemical s TPI, DuPont s Kapton KJ, Ube s Upicel, and Kaneka s Pixeo are typical examples. These are coated on dimensionally stable polyimide films to ensure good physical performance. 

An important criterion of good adhesion is that the adhesive be able to wet the substrate. The copolymers studied vividly demonstrated their ability to wet all types of solid materials (provided the solid is sufficiently heat stable to accept bonding) when, in the molten state, they spread spontaneously on solid PTFE, a material of very low surface energy and thus unwettable by most liquids. 

Guy Rabilloud, worked for years in this industry as General Manager of CEMOTA, a manufacturer of heat stable and electronic adhesives and also has written several excellent books and many patents on the subject. 

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