ISO 14848 pdf download

ISO 14848 pdf download.Plastics — Unsaturated-polyester resins — Determination of reactivity at 130 °C 1 Scope This International Standard specifies a method of measuring – the time required for the temperature of a solution of unsaturated-polyester resin and a catalyst, heated in a thermostatically controlled bath at 1 30 °C, to rise • from 80 °C to 1 40 °C, • from 80 °C to the maximum temperature reached; – the maximum temperature reached; – the speed of the reaction, determined by drawing a tangent at the point of inflection of the temperature/time curve. It applies in particular to unsaturated-polyester resins processed at a temperature higher than 1 00 °C. NOTE – The results are closely linked to the conditions. The aim of this International Standard is to define them as exactly as possible, particularly the following: a) The quantity and form of the resin sample being examined (test tube diameter, height of resin in the tube). b) The rate at which the sample is heated in the bath. For example, the use of a liquid having a relatively low heat capacity (ethylene glycol, silicone oil) leads to slower heating. c) The type of thermometer used. Thermometers having a response slower than that of a thermocouple, and resistance probes having too large a heat-sensitive element, are unsuitable. d) The position of the heat-sensitive element in the resin, both heightwise and relative to the axis of the test tube containing the resin. e) The nature of the catalyst. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 321 9:1 993, Plastics — Polymers/resins in the liquid state or as emulsions or dispersions — Determination of viscosity using a rotational viscometer with defined shear rate 3 Principle Unsaturated-polyester resins are crosslinked by heating with a perester catalyst. A resin/catalyst mixture (in the ratio 1 00 g to 1 g) is placed in a test tube kept in a thermostatically controlled bath at 1 30 °C and – the rise in temperature recorded as a function of...