Rosin polymers derived from

Tackifiers are used in formulating rubber based on adhesives to improve the tack property. Tackifiers are low molecular weight compounds with high Tg. There are two classes of tackifiers the rosin derivatives and the hydrocarbon resins. The rosin derivatives include the rosins, modified rosins, and rosin ester. The hydrocarbon resins consist of low molecular weight polymers derived from petroleum, coal, and plants. The miscibUity between tackifiers and the adhesives is important to choose a tackifier. The viscoelastic property of adhesives can be modified by blending of a miscible tackifier. 

Eatty acid soap was first used for ESBR. Its scarcity prompted the investigation of rosin acids from gum and wood as substitutes (1). The discovery of the disproportionation of rosin allowed rosin acid soaps to overcome the polymerization inhibition of untreated rosin acids. Rosin acid soaps gave the added benefit of tack to the finished polymer. In the 1990s, both fatty acid and rosin acid soaps, mainly derived from tall oil, are used in ESBR. 

Snap. A critical ingredient for emulsion polymerization is the soap, which performs a number of key roles, including production of oil (monomer) m water emulsion, provision of the loci for polymerization (micelle), stabilization of the latex particle, and imputation of characteristics to the finished polymer. Both fatty acid and rosin acid soaps, mamly derived from tall oil, are used in ESBR,... 

Within the specific context of this chapter, renewable resources represent the obvious answer to the quest for macromolecular materials capable of replacing their fossil-based counterparts [2, 3]. This is not as original as it sounds, because, apart from the role of natural polymers throughout our history evoked above, the very first synthetic polymer commodities, developed during the second half of the nineteenth century, namely cellulose esters, vulcanized natural rubber, rosin derivatives, terpene resins , were all derived from renewable resources. What is new and particularly promising, has to do with the growing momentum that this... 

Hooper, K.A. and Kohn,J. (1995) Diphenolic monomers derived from the natural amino acid a-L-tyrosine Large scale synthesis of desaminotyTOS l-t) rosine alkyl esters./. Bioact. Compat. Polym., 10(4), 327-340. 

Liu X and Zhang J (2010), High-performance biobased epoxy derived from rosin , Polym Int 59, 607-609. DOI 10.1002/pi.2781. 

We have found that RMA appears to be a suitable substitute for TMA as a raw material for polymers. Rosin polymers such as polyeste-rimides via RMA or RMID or its derivative possess similar solubility and other characteristics to those synthesized from TMA. The thermal behavior of a polyesterimide (PEI-2) from rosin has been compared with that of TMA-based polyesterimides (Table 4). It is found from Table 4 that the thermal stability of the polyesterimide from RMA is similar to that of TMA. The glass transition temperature,... 

The critical surface tension of a PSA cannot be determined directly, for when the test droplets of low polarity liquids are dissolved in the adhesive the contact angle is not defined. Therefore, this value was derived from those of chemically similar polymers, resulting in 33 mN/m for polyisobutylene and 35-36 mN/m for standard acrylic and rubber-rosin PSAs. 

Latex is a stable dispersion of a polymeric material (Table 8.13) in an essentially aqueous medium. An emulsion is a stable dispersion of two or more immiscible liquids held in suspension by small percentages of substances called emulsifiers. In the adhesives industry, the terms latex and emulsion are sometimes used interchangeably. There are three types of latex natural, synthetic, and artificial. Namral latex refers to the material obtained primarily from the rubber tree. Synthetic latexes are aqueous dispersions of polymers obtained by emulsion polymerization. These include polymers of chloroprene, butadiene-styrene, butadiene-acrylonitrile, vinyl acetate, acrylate, methacrylate, vinyl chloride, styrene, and vinylidene chloride. Artificial latexes are made by dispersing solid polymers. These include dispersions of reclaimed rubber, butyl rubber, rosin, rosin derivatives, asphalt, coal tar, and a large number of synthetic resins derived from coal tar and petroleum. ... 

The aspects relevant to the use of rosin as such, or one of the derivatives arising from its appropriate chemical modification as monomer or comonomer [12-14], have to do with the synthesis of a variety of materials based on polycondensations and polyaddition reactions of structures bearing such moieties as primary amines, maleimides, epoxies, alkenyls and, of course, carboxylic acids. These polymers find applications in paper sizing, adhesion and tack, emulsification, coatings, drug delivery and printing inks. 

Pressure-sensitive adhesives must be very sticky, that is, exhibit high tack. The tack of an adhesive usually reaches a maximum in the range of 40 to 70°C above Tg. Frequently the polymer by itself is not sufficiently tacky for commercial purposes. To solve the problem, people dissolve tackifiers in the adhesive. A tackifier is a compound that increases the Tg of the material while lowering the modulus. By contrast, plasticizers decrease Tg, as well as lower the modulus. Tackifiers are often based on natural product derived rosins, obtained from ground-up pine tree stumps and related materials (95). These rosins are multicycUc steroid-like ring structures. 

Insofar as space is available, renewable monomers usable for polymer synthesis are reviewed. This review, even though quite long, is not perfectly comprehensive, because large numbers of renewable monomers have been found while I have been seeking references. For examples, rosin derivatives, amino acids, and many intermediate products from metabolic pathways of sugar, fatty acid, and proteins are not included. For the same reason, detailed descriptions about the synthesis and properties of each polymer is not included. 

Adhesives are polymers that are initially liquid but solidify with time to give a joint between two surfaces [12,13]. The transformation of fluid to solid can be obtained either by evaporation of solvent from the polymer solution (or dispersion) or by curing a liquid polymer into a network. Table 2.3 lists some common adhesives, which have been classified as nonreactive and reactive systems. In the former, the usual composition is a suitable quick-drying solvent consisting of a polymer, tackifiers, and an antioxidant. Tackifiers are generally low-molecular-weight, nonvolatile materials that increase the tackiness of the adhesive. Some tackifiers commonly used are unmodified pine oils, rosin and its derivatives, and hydrocarbon derivatives of petroleum (petroleum resins). Several polymers have their own natural tack (as in natural rubber), in which case additional tackifiers arc not needed. 

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