Search Results for unsaturated polyesters

This article provides a discussion on polyester coating applications such as powder coatings, can coatings, and automotive paints. It includes an overview, structure, properties, and benefits of vinyl ester resins. The article discusses the additives for both unsaturated polyester and vinyl ester coatings, namely, curing systems, thixotropic agents and fillers. It exemplifies polyester and vinyl ester coating, lining and flooring systems that are used for top-to-bottom protection of industrial plants and equipment. The article also highlights the concerns to be addressed when using polyesters and vinyl esters.

This article provides an overview of the various types of unsaturated polyester resins and low-profile additives. The resins include general-purpose resins, isophthalic resins, bisphenol A fumarate resins, chlorendic resins, and vinyl ester resin. The article describes the mechanical and electrical properties, thermal and oxidative stability, and chemical and ultraviolet (UV) resistance of polyester resins. It concludes with a discussion on the flame-retardant polyester resins.

This article discusses the coating systems categorized by the generic type of binder or resin and grouped according to the curing or hardening mechanism inherent within that generic type. It focuses on the properties, advantages, and limitations of various autooxidative cross-linked resins, thermoplastic resins, and cross-linked thermosetting resins. The autooxidative cross-linked resins include alkyd resins and epoxy esters. The article examines the two types of coatings based on thermoplastic resins: those deposited by evaporation of a solvent, commonly called lacquers, and those deposited by evaporation of water, a class of coatings called water-borne coatings. The coatings that chemically cross link by copolymerization, including epoxies, unsaturated polyesters, urethanes, high-temperature curing silicones, and phenolic linings, are also described.

A thermosetting resin, or thermoset, is a synthetic organic polymer that cures to a solid, infusible mass by forming a three-dimensional network of covalent chemical bonds. Significant applications include construction and thermoset engineering plastics. This article discusses the general and family characteristics of thermosetting resin families, including allyls, aminos (urea formaldehyde and melamine formaldehyde), cyanates, epoxies, polybenzimidazoles, unsaturated polyesters, thermoset polyimides, phenolics, and vinyl esters. It also explains processing methods, including curing and curing agents. The article provides descriptions of commercial product forms and the wide array of applications of thermosetting resins. It also tabulates the performance properties (mechanical, thermal, electrical and chemical resistance) of some families of unfilled or unreinforced thermosetting resins and reinforced or filled grades.

Open molding is the method used in the polymer-matrix composites industry to make thermoset composite products. This article discusses the advantages, disadvantages, and applications of the open molding. It describes the various process of the open molding, such as hand lay-up process and spray-up process. Workmanship for hand lay-up and spray-up processes is reviewed. The article provides information on the matrix-resin materials used for open molding, including unsaturated polyester resins, epoxy vinyl ester resins, and reinforcements. It explains the component design and short- and long-term properties of a fiber reinforced composite laminate depending on material selection and workmanship. The article also presents the basic design guidelines for open molding.

Sheet molding compounds (SMCs) refers to both material and process for producing glass-fiber-reinforced polyester resin items. This article discusses the material components incorporated into the resin paste for desirable processing and molding characteristics and optimum physical and mechanical properties, including catalyst, fillers, thickeners, pigments, thermoplastic polymers, flame retardants, and ultraviolet absorbers. It talks about the mixing techniques available for SMC resin pastes, including batch, batch/continuous, and continuous mixing. The article also outlines the design features and the operations of continuous-belt and beltless machine type SMCs.

This article is a compilation of abbreviations of terms, techniques, standards, compounds, and properties of materials that are relevant to the characterization and failure analysis of plastics.

This article describes the chemistry of phenolic resins and reviews their characteristics and properties for various composites fabrication processes. The fabrication processes include solution/hot-melt process, pultrusion, vacuum infusion, filament winding, sheet molding, and hand lay-up. The article illustrates the manufacturing process of phenolic honeycomb and provides information on the applications of phenolic composites.

This article discusses postconsumer plastics recyclate quantities, the classification of plastics recycling into primary, secondary, tertiary, and quaternary categories, and how the life cycle of plastics is affected by recycling. The recycling processes of polyethylene terephthalate (PET), which accounts for the largest percentage of plastic recycling, high-density polyethylene (HDPE) plastics, the other large-volume plastic recyclate, as well as vinyl resins and polycarbonate resins are described. The life cycle of plastics has four phases: poly formation, part fabrication, product service, and disposal. Landfilling is still the primary method of final disposal, and incineration is another option, but recycling has become a viable alternative. The article presents a comparison between secondary and tertiary recycling.

This article describes the most significant tests to characterize the properties of constituent materials. It discusses the chemical, physical, and mechanical tests for determining the properties of reinforcement fibers and fabrics. The article provides information on some of the basic materials used for thermoset and thermoplastic resin matrices. It reviews the identification of the individual characteristics of thermoset and thermoplastic resin along with the test methods normally used for their determination. The article contains a table that lists properties and tests for uncured and cured thermoset-matrix resins and prepregs.

The design and analysis of aerospace and industrial composite components and assemblies requires a detailed knowledge of materials properties, which, in turn, depend on the manufacturing, machining, and assembly methods used. This article, through several tables and graphs, provides the mechanical properties, physical properties, and service characteristics of representative composite fiber-resin combinations, including thermoplastic matrix composites such as thermoplastic polyester resins, thermoplastic polyamide resins, and thermoplastic polysulfone resins, and thermoset matrix composites such as thermoset polyester resins, thermoset phenolic resins, thermoset epoxy resins, thermoset polyimide resins, and thermoset bismaleimide resins.

This article describes the types of fabrics and preforms used to manufacture advanced and industrial-grade composites and the related selection, design, manufacturing, and performance considerations. It shows typical properties of one mixed graphite/aramid fabric type. The article provides a sampling of styles commonly used in aerospace and industrial composite materials applications. It discusses the chemistries of high-performance prepreg resin and reviews fiber tow, yarn, and roving characteristics for towpreg. The article also discusses the tape composite manufacturing processes generally included in three significant categories: hand lay-up, machine-cut patterns laid up by hand, and automatic machine lay-up.

This article discusses the materials and properties of polymer-matrix composites to characterize each generic material according to its composition and method of manufacture. It contains a table that lists the key physical, mechanical, thermal, and electrical properties, and in-service conditions of concern for resin-matrix composites. Axes definitions, symbols, and special property calculations for composite material property tests are reviewed. The article provides an overview of the performance capabilities of selected polymer-matrix composite materials such as thermoplastic-matrix composites and thermoset-matrix composites. The thermoplastic-matrix composites include thermoplastic polyester resins and fiber resin composites; thermoplastic polyamide resins and fiber-resin composites; and thermoplastic polysulfone resins and fiber-resin composites.

Pultrusion is an automated process for manufacturing composite materials into continuous, constant cross-sectional profiles. The article provides an overview of the pultrusion process and the wide range of materials that can be used to provide a broad spectrum of composite properties. It discusses the mechanical, physical and material properties of pultruded products, and the orientation options available to utilize the properties advantageously. The article also provides guidelines for designing pultruded products.

This introductory article describes the various aspects of chemical structure that are important to an understanding of polymer properties and thus their eventual effect on the end-use performance of engineering plastics. The polymers covered include hydrocarbon polymers, carbon-chain polymers, heterochain polymers, and polymers containing aromatic rings. The article also includes some general information on the classification and naming of polymers and plastics. The most important properties of polymers, namely, thermal, mechanical, chemical, electrical, and optical properties, and the most significant influences of structure on those properties are then discussed. A variety of engineering thermoplastics, including some that are regarded as high-performance thermoplastics, are covered in this article. In addition, a few examples of commodity thermoplastics and biodegradable thermoplastics are presented for comparison. Finally, the properties and applications of six common thermosets are briefly considered.

Molding compounds are plastic materials in varying stages of pellets or granulation that consist of resin, filler, pigments, reinforcement, plasticizers, and other ingredients ready for use in a molding operation. This article describes the material components and physical properties of sheet molding compounds (SMC). The three types of resin paste mixing techniques, such as batch, batch/continuous, and continuous, for an SMC operation are reviewed. The article discusses the design features and functional operations of the two types of SMC machines, namely, continuous-belt and beltless machines. It explains the formulation and processing of bulk molding compounds and reviews molding methods for bulk molding compounds, including compression, transfer, and injection molding. The effects of the fiber type and length and the matrix type on thermoset bulk molding compounds are discussed. It describes the four injection molding processes of injection molding compounds such as feeding, transporting, injecting, and flowing.