Mastic resin composition

Despite the complexity of the chemical composition of the resinous materials, in a few minutes such techniques provide a mass spectral fingerprint, which highlights the compounds that are the main components in the sample. They avoid any sampling treatment before analysis. They have thus enabled diterpenoid resinous materials from Coniferae, and several triterpenoid materials to be clearly identified. In particular, the DE-MS technique is able to distinguish between different triterpenoid materials such as mastic resin, frankincense resin and birch bark tar. In fact, using PCA on DE-MS mass... 

The resin composition was indeed found to influence the ageing processes in mastic, the polymer fraction was shown to reduce the oxidation of triterpenoids (Figure 5.8). This was found for both natural ageing [33, 36] and artificial ageing. Because the polymer, a polymyrcene, contains many double bonds that can easily be oxidised [42], it might act as a radical stabiliser. The mastic samples shown in Figure 5.8 were obtained from three aliquots of the same mastic solution, the polymer part of the first aliquot was removed and added to the third. 

Mastic mas-tik [ME mastik, fr. L mastichcy fir. Gk mastiche, prob. back-formation fr. mastichan] (14c) n. (1) A solid resinous material obtained from the mastic tree Pis-tacia lentiscus) and used in adhesives and lacquers. (2) Asphalt mastic a composition of mineral matter with resin and solvent. 

The botanical species exploited in the past for the collection of resins vary according to the geographical area, and thus, the availability of adequate reference materials of a known botanical origin is crucial for resin identification. Pine resin and resin-derived pitch, mastic, frankincense, myrrh, benzoe, and birch bark tar are the most common terpenoid materials in archaeological artifacts from the Mediterranean area. Terpenic resin composition depends on aging and exposure to air and light, so the biomarkers used for their identification are... 

Base-plate wax compositions are generally regarded as trade secrets. A substantial percentage of paraffin is usually present, probably 50—80 wt %. Beeswax [8012-89-3] camauba wax [8015-86-9] ceresin, microcrystalline waxes, Acrawax C (Glyco Products Co. Inc.), mastic gum, rosin [8050-09-7] and synthetic resins may make up the balance of the formulation. Base-plate waxes are generally sold in sheet form about 1.3 mm thick, 75 mm wide, and 140 mm long. 

The compositions of sheet and shape waxes are also trade secrets. However, they are blends of various proportions of paraffin, microcrystalline waxes, camauba wax, ceresin, beeswax, gum dammar, mastic gum, and possibly other resins. Sheet waxes are marketed in square sheets approximately 80 by 90 mm. Various thicknesses are available from 32 gauge (0.5 mm) to 14 gauge (1.63 mm). 

Resins are also used for permanent tooth-colored veneers on fixed prostheses, ie, crown and bridges. Compositions for this application include acryflcs, vinyl—acryflcs, and dimethacrylates, as well as silica- or quartz-microfilled composites. The resins are placed on the metallic substrates of the prostheses and cured by heat or light. These resins are inexpensive, easy to fabricate, and can be matched to the color of tooth stmcture. Acrylic facings do not chemically adhere to the metals and are retained only by curing the resin into mechanical undercuts designed into the metal substrate. They have relatively low mechanical strength and color stability, and poor abrasion and strain resistance they also deform more under the stress of mastication than porcelain veneers or facings. 

The protective medium against fire discussed here is a water-insoluble mastic. Mastic is defined as a material of heavy paste consistency which can be applied with a putty knife, trowel, brush, or heavy duty spray equipment to yield a coating from 1/32 inch to one inch or more. These mastics are of mineral composition, bound by an organic resinous medium, and dry to ultimate hardness by the volatilization of an organic solvent. They are further characterized by high impact strength, and assistance to abrasion, water, and many chemicals. 

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