Compressive strength: polyesters

The type of acid present in the polyester influences the compressive strength. Polyesters based on aliphatic saturated acids have a low compressive strength. 

P) 3-P diluted with acetone, wood loaded and heated. Grafted polyester side chains on swollen cell wall cellulose. Carbonyl end groups reacted with copper or zinc to decrease fungi attack. Compression strength increase. 

As shown in Table VIII, about the same compressive strength can be reached with DCP-modified sulfur concrete as with polyester concrete. The temperature loading lies in about the same range in both cases. 

Consolidated polyester shows different physical characters owing to the ratio of the quantity of the ester to that of the monomer the specific gravity is 1.2tensile strength 350 700 kg/cm, compressive strength 850 1700 kg/cm. Generally it is hard and brittle. Its resistance to inorganic acids and alkalis is weak. 

Long-term exposure to a number of different chemicals reveals that iso-phthalic polyesters give products with a higher chemical resistance compared with phthalic polymers. Use of hydrogenated bisphenol A as the glycol component offers additional improvement to the compressive strength (Boeing, 1969). 

Owing to this rapid cure, a compressive strength of 40 N/mm is possible within 2 h at temperatures down to 4°C (Shaw, 1993a). The properties of polyester binder depend primarily upon the chemical composition of the polyester resin component. Typical physical properties of cured polyester binders for concrete overlays are given in Table 9.3 (ACI, 1993). 

Matrix resins to be used for syntactic foams include thermosetting resins and thermoplastic resins, as shown below. Epoxy resin, unsaturated polyester and phenolic resin have been the resins of choice for industrial applications because the resulting foams have remarkably high compressive strengths. Examples of the resins used are given below. 

Typical properties of RPUMRPE mortar in comparison to the hybrid recycled polyester (HRPE) mortar and recycled polyester (RPE) are presented in Table 6. The HRPE is hybrid polymer of recycled polyester and polyurethane which comes from F2 hybrid resin part A made by Amoco. The RPE is recycled polyester made by Alpha corporation. The bond, tensile and compressive strength, modulus of elasticity and shrinkage of these three kinds of polymer mortar were measured at 4, 8, 12, and 24 hours respectively. 

Polymer concrete samples of four compositions (Table 1.2) measuring 4 x 4 x 16 cm are prepared. Control samples were placed in a desiccator containing moisture absorption silica gel composition. Other samples were in environments with various humidity. The influence of environmental humidity on the compressive strength, modulus elasticity, and moisture absorption of furfurol-acetone, epoxy, polyester, and rubber (RubCon) polymer concrete samples are shown in Tables 1.3-1.5 and Figures 1.4 and 1.5. 

The maximal decrease in compressive strength (up to 40%) is observed in the polyester composites, which is caused by destruction of the bonds between polyester molecules and between binder and filler. 

In Table 21.1 one can see that the cohesive energy of aromatic units is higher than that of ether or ester units. The presence of aromatic rings (especially in polyether and in polyester polyols) leads to a strong increase in some physico-mechanical properties, such as tensile strength and compression strength, with a decrease in elastic properties, such as ultimate elongation [7]. 

The physical properties of a typical room temperature-cured polyester concrete is as follows Barcol hardness (50), tensile strength (500 kg cm 2), elongation (0.45%), compressive strength (1400 kg cm 2) flexural strength (1050 kg cm ) and heat deflection (41"C). The latter may be Increased by 30 by the use of fumaric acid Instead of maleic acid. 

Proposal of Ohama s styrene-unsaturated polyester ratio rule (law) in the compressive strength prediction for polyester concrete by using styrene-unsaturated polyester ratio or unsaturated polyester-styrene ratio [36]... 

Kou et al., reported using a hyperbranched acrylated aromatic polyester as a modifier in UV eurable epoxyacrylate resin. The material is compatible with the epoxy-acrylate resins. They found that the photopolymerization rate of the resin is promoted by this modifier. Also, the shrinkage of the resin was redueed. At the same time, the tensile, flexmal, compressive strength, and thermal properties of the ultraviolet light eured films are greatly improved. 

As shown by Table 4, the compressive strength of aromatic polyamides, PBO and PBT fibers is considerably higher than that of aromatic polyester or ultra high-molecular weight (UHMW) polyethylene fibers [216, 217]. The compressive strength of PpPTA fibers increases with increasing modulus, as is shown in Fig. 27,... 

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