Polyester resins content

Tetrachlorphthalic Anhydride and Tetrachlorphthalic Acid. Tetrachlorphthalic anhydride [117-08-8] (TCPA) is manufactured by the ferric chloride catalyzed chlorination of phthalic anhydride. The relatively low chlorine content and the lower flame retardant efficiency of the aromatic chlorides limit use to unsaturated polyester resin formulations that do not requite a high degree of flame retardancy. 

Cured amino resins are far too brittle to be used alone as surface coatings for metal or wood substrates, but in combination with other film formers (alkyds, polyesters, acryUcs, epoxies) a wide range of acceptable performance properties can be achieved. These combination binder coating formulations cure rapidly at slightly elevated temperatures, making them well suited for industrial baking appHcations. The amino resin content in the formulation is typically in the range of 10—50% of the total binder soHds. 

Several factors were utilized in bringing formaldehyde release down. In particular, resin manufacturer executed more careful control of variables such as pH, formaldehyde content, and control of methylolation. There has also been a progressive decrease in the resin content of pad baths. The common practice of applying the same level of resin to a 50% cotton—50% polyester fabric as to a 100% cotton fabric was demonstrated to be unnecessary and counter productive (89). Smooth-dry performance can be enhanced by using additives such as polyacrylates, polyurethanes, or siUcones without affecting formaldehyde release. 

By depolymerizing PET waste with a polyol and subsequently condensing the oligomeric product with a polycarboxylic acid or anhydride, polyester resins are produced which have wide industrial applications. Depending on the polyol and polycarboxylic acid or anhydride used, saturated resins, alkyd resins, or unsaturated resins are obtained. PET wastes have been used for the production of alkyd resins in water thinnable paints. The materials obtained from the reaction of PET with a mixture of fatty acids high in linoleic acid content and trimethylolethane have been used in the preparation of water-dispersible coatings. Products of the depolymerization of PET with trimethylolpropane and pentaerythritol are used in the manufacture of high-solids paints. In the first step, PET is depolymerized with trimethylopropane and pentaerythritol at temperatures of 230-240°C. The final paint compositions contain 30-50% of PET depolymerization products.12... 

Whereas McGee [188] did not verify any effect of particulate fillers (i.e., glass, calcium carbonate, and aluminum) on the reaction kinetics, Lem and Han [185], working with calcium carbonate and clay in an unsaturated polyester resin, concluded that the reaction rate increases by increasing the filler content. 

Twenty-eight of fifty-four samples purchased were found to have coatings made from polyester resins and so their contents were analysed for TPA and IPA. Analysis was by GC-MS after extraction and derivatisation to form the dimethyl esters of TPA and IPA. Included in the analytical quality assurance steps taken was participation in a check-sample exercise whereby four samples were supplied by a second laboratory and analysed blind. The performance of the testing laboratory was assessed from the accuracy and precision of their measurements and was demonstrated to be acceptable. 

Here, 7 is the magnitude of the strain rate tensor and C/ is a phenomenological coefficient which models the interactions between the fibers, usually referred to as the Folgar-Tucker interaction coefficient. The coefficient varies between 0, for a fiber without interaction with its neighbors, and 1, for a closely packed bed of fibers. For a fiber reinforced polyester resin mat with 20-50% volume fiber content, CV is usually between 0.03 and 0.06. When eqn. (8.153) is substituted into eqn. (8.152), the transient governing equation for fiber orientation distribution with fiber interaction built-in, becomes... 

Two resins were used to do the first study on laminate construction. The first was a brominated epoxy vinyl ester resin with antimony pentoxide and the second was a brominated unsaturated polyester resin. They were both promoted to cure at room temperature with methyl ethyl ketone peroxide catalyst. The panels were then postcured at 250°F (121°C) for 8 h. Panels were prepared that varied in glass content from 25% to 70% and panel thickness varying from 0.05 in. to 0.25 in. and were tested at the same testing facility. A summary of the FSI test data for the first set of panels tested are shown in Figures 23.1 and 23.2. This graph in Figure 23.1 plots the FSI value versus the panel thickness. This data would indicate that the thickness of the test panel has no effect on the measured... 

PET is useful polymer used for fiber, film, and plastic containers such as carbonated beverage bottles. Recently, the recycling of polymers such as PET after use is attracting the attention of many researchers aware of environmental problems and wishing to find ways to save earth resources. Previous studies showed that unsaturated polyester resins can be economically prepared from recycled PET and the resins may be useful for resin concretes (1 4). However, there is little information on the molecular features of the UPE resins. Thus, we synthesized various UPE resins from PET. Especially, the PET content, chain flexibility and degree of unsaturation of the resins were systematically varied and the effects of those variables on the mechanical properties of the cured resins and polymer mortars made therefrom were studied. 

Various UPE resins based on recycled poly ethylene terephthalate(PET) were prepared and the properties of the polymer mortar made with the UPE as well as those of the cured resin itself were investigated. It was found that degree of unsaturation of the resins was the most important property affecting thermal and mechanical properties of the cured resin and PM. The cured unsaturated polyester resin or polymer mortar made from resins of higher unsaturation, i.e., less PET content or adipic acid content in the resin, showed higher glass transition temperatures,... 

The experimental unsaturated polyester resins used in this study were supplied by several chemical companies since the PET chemical conversion into unsaturated polyester could not be done at the University of Texas laboratories. These resins were prepolymers with high viscosity. They were therefore diluted with styrene to reduce their viscosity and allow their further cure to a solid (polymer) upon the addition of suitable free radical initiators and promoters. The typical styrene content varied between 30 to 40% of the total resin weight, and viscosities were in the range of 100 to 1000 cps. 

Figure 16.13. Viscosity of polyester resin filled with calcium carbonate and microspheres (total content of filler (CaCOs+microspheres) is 60 wt%). [Data courtesy of Abrasivos Y Maquinaria, SA, Barcelona, Spain] ...

The polymerization kinetics were studied via time-conversion relationships at different dose rates (Figures 6-9). The radiation curing was carried out at room temperature in closed aluminum capsules. Percent monomer conversion was determined gravimetrically for N-vinylpyrrolidone. Evaporation was accomplished under vacuum in a ventilated oven at 50 °C until the weight was constant. For butyl methacrylate and polyester resins, the residual monomer content was determined by gas chromatographic analysis after immersion of the cured products in acetone. 

Type of Polyester Resin Acid Value Specific Gravity (20°C) Viscosity (20°C,cP) Styrene Content (%)... 

Fig. A shows the effects of CoOc and MEKPO contents on setting shrinkage of polyester resin concrete. The setting shrinkage increases with rising contents of CoOc and MEKPO. In particular, the shrinkage is remarkably affected by MEKPO (catalyst) content rather than CoOc (accelerator) content.

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