Adhesives and sealants based

Application of adhesives and sealants based on hybrid NIPU (HNIPU) for pasting metal surfaces is important in various industries [24], Various compositions of adhesives and sealants were developed based on research results. Their physical-chemical properties are given in Table 4.2. 

Silaprene . [Uniroyal] Industrial adhesives and sealants based on chloro-prene, PVC acrylic, nitrile, natural rubber, SBR, PC, ABS, urediane, or epoxy or blends. 

Today all formulated adhesives and sealants combined represent a global tonnage of 8.5 Mio mto (dry, annually), and are projected to grow to 10.2 Mio mto by 2010. These figures do not include typical binders for paper manufacture and for use in the woodworking industry. From this tonnage a mere 15.5% (2006), respectively 15.0% (2010), represent adhesives and sealants based on natural origin with or without additional chemical modification. 

Adhesives and sealants based on renewable sources show a number of advantages, but also major disadvantages that effectively limit their broader use at present. On the positive side they usually show an excellent bio-compatibility given that their chemical modification did not completely alter this. Natural-based products in general show a positive Greenhouse Gas (GHG) balance, and thus do not directly contribute to climate change. They show a fairly good price/performance ratio, usually are available in sufficient quantity and show no or low toxicity. 

There is on the other hand room for stopping the downturn trend or a further decline of adhesives and sealants based on renewable resources ... 

Uses Tackifier resin for water-based adhesives and sealants based on acrylic, S/B, nat. rubber, neoprene, and PVAc, esp. for pressure-sensitive adhesives, and for coatings Features Solv.-free... 

Chapter 7 Adhesives and sealants based on VAE emulsions, by Wacker company,... 

The effect of environmental legislation on the adhesives and sealants market in Europe is outlined. More efficient water-based and hot melt methods it is said are being developed in response to the tightening of environmental legislation. A report by Frost Sullivan is said to indicate further changes and developments in the core adhesives, sealants and related products market. 

Fissure sealants are clear, low-viscosity, photocurable liquids, based on a mixture of fefrafunctional and difuncfional mefhacrylafes. Other dental photocurable materials are cements, adhesives, and denture base resins. " ... 

The base material producers are usually large chemical or material companies that manufacture products for broad markets such as petrochemicals or plastics. When demand warrants, they will produce materials specifically for the adhesive and sealant formulators. 

Fumed silica is often used in 100 percent solids, liquid polymers. With epoxy adhesives and sealants only a few percent by weight of the additive will eliminate common problems such as slumping and separation. The fumed silica also raises the effective viscosity of the base resin to prevent other components from settling while the extrudability or spreadabil-ity is unaffected. Also note that fumed silica provides a surface that is free of texture. This is important in architectural-grade paints and sealants. 

Based on the numbers in Figures 1 and 2, by 1985 RIM and RRIM will require approximately 50 M lbs. of monomeric MDI, which is about one-third of the monomeric MDI supply in 1985 (Table IX based on 20-25% of 85% nameplate capacity, excluding ARCO capacity, = 137-171 M lbs. monomeric MDI). This will leave about 100 M lbs. of monomeric MDI for cast elastomers, thermoplastic polyurethanes, shoe soles, semi-rigid foams, and some adhesives and sealants, a monomeric MDI supply which should be more than sufficient for these applications. As RRIM grows, a need for capacity expansion can be seen in the late 1980 s. No effects on the market will be seen from PUR-SMC until after 1985, and at the present time meaningful projections are impossible. 

Dilexo . [Condea Chemie GmbH] Copolymer disp ions base materials for paints, plasters, adhesives, and sealants. 

Oppantd . [BASF BASF AG] Polyisobutylene fw adhesives and sealants, elec, insulating oils, bases for diewing gums, for prod, ttfdanippiotrf courses containing fillers in construction industry. 

It was not until the commercialization of synthetic plastics resins in the 1930s that an almost unlimited variety of base materials became available for compounding into adhesives and sealants. Most of the thermoplastic resins were soluble in organic solvents and were used as solvent adhesives for molded plastic articles of the same base composition and sometimes for other materials. Poly(vinyl chloride) (PVC), a thermoplastic developed in 1927, is used today in solvent formulations to bond PVC articles such as coated fabrics, films, foams, and pipe. In the early 1930s, phenolics came into importance as adhesive resins. Before that time they were used as coating varnishes [9, p. 239). About 1931 development of the use of a new phenolic resin for plywoods and veneers began [9, p. 239]. 

Silicone adhesives were introduced commercially in 1944 [5, p. 213]. In 1960 the silicone sealants were introduced to the construction industry [11, p. 86]. Silicones are useful at both high and low temperatures and are available today as solvent-based moisture-curing adhesives, one-part moisture-curing adhesives and sealants, two-part curing adhesives and sealants, and pressure-sensitive adhesives. 

From the chemists has come the classification of adhesives and sealants by chemical type, and from the mechanical engineers the classification as either structural or non-structural. Neither is a pure system, since many adhesives and sealants have more than a single chemical base resin, and many structural -based resin systems are used in non-structural applications. In a chapter entitled Structural Adhesives we are told that the term structural adhesive came into general use in the 1960 1970 period, but to this day all definitions are inadequate [9, Chap. 7]. Adhesive manufacturers and their advertising... 

Thermoplastic rubber block copolymers, with completely new adhesive performance, were developed in 1965 [21]. The first commercial product was Shell Chemical s Kraton 101, of styrene polybutadiene-styrene composition. This development led to the carboxy-terminated nitrile (CTBN) rubber modifiers used to flexibilize epoxy and other brittle resin adhesives in the late 1960s. Today, the thermoplastic rubber block copolymer adhesives are used in hot melt-, solvent- and water-based adhesives, and as hot melt- and solvent-based sealants. Major applications are as pressure-sensitive adhesives, construction adhesives and sealants, and general assembly adhesives. 

One of the more interesting uses of modern adhesives and sealants is by museums in the repair and restoration of antiquities. Nitrocellulose-based adhesives are widely used in such applications, as are epoxies and polyurethanes. In the United States, the Guggenheim Museum has made exhaustive, expensive, and highly scientific evaluations of the effects on durability of such repairs on irreplaceable artifacts from the past. Thus adhesives and sealants have come full circle back to some of their original uses. 

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