8/ What is the prinčipal difference between the two subdivisions of the polymeric composites: thermosets and thermoplastics? 8.1. Thermoset matrix - polyester, epoxide, phenol formaldehyde or other -...

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Extracted text: 8/ What is the prinčipal difference between the two subdivisions of the polymeric composites: thermosets and thermoplastics? 8.1. Thermoset matrix - polyester, epoxide, phenol formaldehyde or other - after curing becomes insoluble and infusible. On the contrary, thermoplastic matrix hardens as a result of cooling of the polymer melts. 8.2. The difference between the two main types polymer matrices is the use of continuous carbon fibres as reinforcement of thermosets and chopped glass fibres in the thermoplastic composites. 8.3. The use of reactive and thermoplastic resins for activating of the surfaces of reinforcing fillers. 9/ In what range vary the diameters of the glass fibres in the polymer composites reinforced with them? 9.1. The reinforcing glass fibers for plastics are 0,1 – 0,2 mm. in diameter; 9.2. The diameters of the reinforcing glass fibers for plastics are at about 3 -4 um. 9.3. The diameters of the reinforcing glass fibers for plastics vary from 8 to 12 µn.