Hardness heat distortion temperature

Polycarbonate/ABS Notched impact resistance, hardness, heat-distortion temperature... 

Rockwell hardness Heat distortion temperature R118 R112 Rill R108 R107 R83... 

Flame, impact, and chemical resistance Flame resistance, impact resistance, processability Notched impact resistance, hardness, heat-distortion temperature Lower cost... 

SAN resins possess many physical properties desked for thermoplastic appHcations. They are characteristically hard, rigid, and dimensionally stable with load bearing capabiHties. They are also transparent, have high heat distortion temperatures, possess exceUent gloss and chemical resistance, and adapt easily to conventional thermoplastic fabrication techniques (7). 

Ultem PEI resins are amber and amorphous, with heat-distortion temperatures similar to polyethersulfone resins. Ultem resins exhibit high modulus and ate stiff yet ductile. Light transmission is low. In spite of the high use temperature, they are processible by injection mol ding, stmctural foam mol ding, or extmsion techniques at moderate pressures between 340 and 425°C. They are inherently flame retardant and generate Httie smoke dimensional stabiUties are excellent. Large flat parts such as circuit boards or hard disks for computers can be injection-molded to maintain critical dimensions. 

The use of ABS has in recent years met considerable competition on two fronts, particularly in automotive applications. For lower cost applications, where demands of finish and heat resistance are not too severe, blends of polypropylene and ethylene-propylene rubbers have found application (see Chapters 11 and 31). On the other hand, where enhanced heat resistance and surface hardness are required in conjunction with excellent impact properties, polycarbonate-ABS alloys (see Section 20.8) have found many applications. These materials have also replaced ABS in a number of electrical fittings and housings for business and domestic applications. Where improved heat distortion temperature and good electrical insulation properties (including tracking resistance) are important, then ABS may be replaced by poly(butylene terephthalate). 

Its greatest deficiency is processability—it is hardly thermoplastic at all Hercules sells mill shapes which must be machined into 6nd products, while Formica has developed a continuous compactionsintering machine for producing it in sheet and laminate form (3). In addition, its modulus, strength, and heat distortion temperature are no better than conventional medium-density polyethylene. Bar, plate, and rod stock sell for 2 up, before machining. 

Durometer hardness, Shore, D scale Heat-distortion temperature, °C At 0.455 MPaa At 1.82 MPaa... 

Many different methods can be used to measure the degree of crosslinking within an epoxy specimen. These methods include chemical analysis and infrared and near infrared spectroscopy. They measure the extent to which the epoxy groups are consumed. Other methods are based on the measurements of properties that are directly or indirectly related to the extent and nature of crosslinks. These properties are the heat distortion temperature, glass transition temperature, hardness, electrical resistivity, degree of solvent swelling and dynamic mechanical properties, and thermal expansion rate. The methods of measurement are described in Chap. 20. 

HIPS products however do not have sufficient impact strength for many uses. SkiHed researchers agree that HIPS with impact strength approaching 7.5 ft-lbs/inch notch can be prepared by adding more rubber. However the hardness, flexural modulus, tensile, and heat distortion temperatures are then drastically reduced. 

HDT, heat distortion temperature TS, tensile strength FS, flexural strength IS, impact strength RH, Rockwell hardness CS, compressive strength WA, water absorption THSW, thickness swelling LSW, linear swelling. 

Crosslinking is a common technique used to develop solvent resistance in the final coating and to increase hardness or heat distortion temperature (necessary if the thermoplastic vinyl coating required sanding... 

Tensile strength (psi) Compressive strength (psi) Flexural strength Izod impact strength Hardness, Rockwell Heat distortion temperature H2O absorption 24-hr immersion Resistance to 10% NaOH... 

Strength, hardness, solvent resistance, heat distortion temperature, extent of chemical reaction, all... 

The process is slow except at high temperatures. Considering unreinforced resins hrst, absorption causes dimensional changes and softening, that is, a reduction in surface hardness and in modulus. The glass transition temperature and associated heat distortion temperature of the resin fall substantially, lowering the maximum permissible use temperature of the resin [23]. 

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