Additives for Thermoplastics

E-glass fibre R-glass fibre Aramid fibre Carbon fibre 

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E. Termine and K. G. Taylor, "A New Intumescent Flame Retardant Additive for Thermoplastics and Thermosets," n Additive Approaches to PolymerModification, SPE RETEC Conference Papers, Toronto, Ontario, Canada, Sept. 1989. 

MixedPhosphona.te Esters. Unsaturated, mixed phosphonate esters have been prepared from monoesters of 1,4-cyclohexanedimethanol and unsaturated dicarboxyhc acids. Eor example, maleic anhydride reacts with this diol to form the maleate, which is treated with benzenephosphonic acid to yield an unsaturated product. These esters have been used as flame-retardant additives for thermoplastic and thermosetting resias (97). 

Polyisobutylene is produced ia a range of mol wts, and has found a host of uses. The low mol wt Hquid polybutenes have appHcations as adhesives, sealants, coatings, lubricants, and plasticizers, and for the impregnation of electrical cables (7). Moderate mol wt polyisobutylene was one of the first viscosity-iadex modifiers for lubricants (8). High mol wt polyisobutylene is used to make uncured mbbery compounds, and as an impact additive for thermoplastics. 

Aromatic carboxylic dianhydride chain extenders (e.g. PMDA) are a low-cost way of converting recycled PET flakes into high-IV crystalline pellets that can be used in high-value applications (e.g. bottles, strapping, foam, engineering alloys/compounds, etc.) (see Figure 14.2). PMDA is an effective chain extension additive for thermoplastic polyesters such as PET and PBT. It is suitable for the following applications ... 

In general, any additives that are common in the polyolefin sector can be used to achieve the desired properties. We will summarize additives for thermoplastic metathesis polymers. These include (6) ... 

A Concise Introduction to Additives for Thermoplastic Polymers by Johannes Karl Fink. Published 2010. ISBN 978-0-470-60955-2. Written in an accessible and practical style, the book focuses on additives for thermoplastic polymers and describes 21 of the most important and commonly used additives from Plasticizers and Fillers to Optical Brighteners and Anti-Microbial additives. It also includes chapters on safety and hazards, and prediction of service time models. 

Medium and high molar mass polyisobutenes are used essentially as basic materials for sealants and adhesives, as flexibility improvers for waxes and bitumen and as impact additives for thermoplastics. The low toxicity allows their use in chewing gum formulations. Detailed production is not disclosed but it is probably limited to a few tenths of kilotons. Main producers are BASF (Oppanol Bl-3, B10-50, B80-246) and Exxon Chemical (Parapol, Vistanex LM and MM). 

Figure 8.3 Structures of hindered phenol antioxidants. (Reproduced with permission from J. Fink, A Concise Introduction to Additives for Thermoplastic Polymers, Wiley-Scrivener Publishing, Salem, MA, 2010).

A Concise Introduction to Additives for Thermoplastic Polymers by Johannes Karl Fink. Published 2010. 

Spheriglass . [Potters Industries] Solid glass spheres additive for thermoplastic and thermosetting resin systems enhance processing for automotive, chemical, electronic, industriaL engineering, and photogrtq>hic industries. 

BuchR, etal. Silicone-based additives for thermoplastic resins providing improved mechanical processing and fire properties. Technical paper (www.specialchem4 polymers.com) Dow Corning Corp. 2001 (downloaded 31 July 2008). 

There is a broad range of additives for thermoplastics. Some of the more important additives include plasticizers, lubricants, anti-aging additives, colorants, flame retardants, blowing agents, cross-linking agents, and UV protectants. Fillers are also considered additives but are covered in Chap. 1. 

A related use is to produce the diglycidyl ether of tetrabromobisphenol A, which can be used as such in epoxy thermoset fabrication but is mainly reacted with methacrylic acid to make flame-retardant vinyl ester resins. These are useful for making fiber-reinforced corrosion resistant containers and ducts. The diglycidyl ether can also be chain extended with more tetrabromobisphenol A to make a family of, mainly, additives for thermoplastics. 

Because of the commercial availability of phenylphosphonyl dichloride flben-zene phosphorus oxydichloride, BPOD), much work has been done on this intermediate to make polymeric phosphonates as flame-retardant thermoplastics or as additives for thermoplastics. In an early study, Toy (90) carried out the polycondensation of BPOD and dihydric phenols in a melt. Coover and McConnell added the use of an alkaline earth halide catalyst (91). For enhancement of the flame-retardant effectiveness as flber additives, tetrabromobisphenols were used to make polyphosphonates (92). Various cocondensed polyesters with both phosphonate ester units and dicarboxylic ester units have been described and patented. 

Compounding and Special Additives for Thermoplastic Copolyester Elastomers... 

One of the main limitations of intrinsically conductive polymers (ICP s) towards their wide application as conductive additives for thermoplastics is their poor thermal-oxidative stability at typical melt processing temperatures (i.e., above 200 °C). On the other hand, the use of high surface area carbon blacks (CB) as conductive additives is limited due to the increased melt viscosity of their blends with thermoplastics. Eeonomers are a new class of thermally stable, chemically neutral, and electrically conductive composites made via in-situ deposition of conductive polyaniline (PANI) or polypyrrole (PPY) on CB substrates. Eeonomer composites are more stable (up to 300 °C) than pure ICP s and more easily processible with thermoplastics than CB. Use of Eeonomers as conductive additives for plastics lead to compounds with improved electrical, mechanical, and processing properties. By varying Ae conductive polymer to CB ratio, it is possible to fine tune the polarity of Eeonomer composites and achieve very low percolation thresholds. This control is possible because of preferred Monomer localization at the 2D phase boundary of the immiscible polymer blends. 

Eeonomers are a new class of conductive additives for thermoplastics made via in-situ deposition of intrinsically conductive polyaniline or polypyrrole on carbon black. Eeonomers are highly thermally stable, pH neutral conductive materials that are compatible with the chemistry and melt processing conditions of acid sensitive polymers. Compounding studies with thermoplastics indicate better electrical, mechanical, and melt flow properties of Eeonomer blends as compared to blends with traditional carbon blacks. In co-continuous plastic blends it was possible to fine tune the polarity of Eeonomer by varying the conductive polymer to CB ratio. The same variation affords very low percolation thresholds due to preferred Eeonomer localization at the 2D phase boundary. 

Le Bras, M. Bourbigot, S. Felix, E. Pouille, F. Siat, C. Traisnel, M. Characterization of polyamide-6-based intumescent additive for thermoplastic formulations. Polymer 2000, 41(14), 5283-5298. 

Solid glass spheres provide a unique additive for thermoplastic and thermosetting resin systems. Their multiple benefits, including enhanced processing and reduced manufacturing costs are outlined below. 

Klingert B. Influence of stabilizers on light and thermal stability of filled polypropylene. Functional fillers and additives for thermoplastics and rubber conference. Berlin September 1994. p. 26-28. 

In addition, there is a basic difference between additives for thermoplastic material and additives for thermosetting resins. Likewise, a curing agent and an accelerator may be considered as an additive. However, these types of additives are not usually considered as additives in the common sense, so they are not taken up into this book. 

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