Resin temperature

When the resin temperature drops below the boiling point of the reactive diluent (usually styrene) the resin is pumped into a blending tank containing suitability inhibited diluent. It is common practice to employ a mixture of inhibitors in order to obtain a balance of properties in respect of colour, storage stability and gelation rate of catalysed resin. A typical system based on the above polyester fomulation would be ... 

Twenty-four hundred grams (25.6 mol) of phenol, 1645 g of 37 wt % formaldehyde (20.3 mol), and 30 g (0.33 mol) of oxalic acid were charged to a 5-L, three-necked resin kettle. The mixture was stirred and refluxed until the distillate was free of formaldehyde (1-3 h) then water was distilled from the mixture until the resin temperature reached 154°C. The viscosity of the resin at this point at 150°C was such diat 105 s was required for flow in an inclined plate test. The pressure was slowly reduced while a slow current of nitrogen was bubbled through the resin, and the mixture was heated to 175°C at 6 mm Hg. Approximately 6 wt % phenol was recovered then the resin was poured into an aluminum dish and cooled. The resin had a melt viscosity of 510 s at 150°C. 

T0 equilibrium transition temperature or initial resin temperature, K... 

Nakatani M. Scale-up theory for twin-screw extruder, keeping the resin temperature unchanged. Adv Polym Technol 1998 17(l) 19-22. 

Fig. 117. Low-temperature explosions of mixtures of potassium perchlorate with some combustible substances /—with polyester resin (temperature of the thermostat 296°C), //—with ethylene glycol (temperature of the thermostat 241°C), (according to Gro-...

A higher resin temperature and a heated mold will prolong the flow time of the plastic, including layers close to the surface. This will enhance the disorientation of the aluminum flakes and thereby the optical appearance of the molded part. 

Resin Temperature- Density IB Thickness Swell Dried4... 

Fine powder PTFE is susceptible to shear damage, particularly above its transition point (19°C). Handling and transportation of the containers could easily subject the powder to sufficient shear rate to spoil it if the resin temperature is above its transition point. The phenomenon caWedfibrillation (Fig. 5.26) occurs when particles rub against each other, in which fibrils are pulled out of the surface of PTFE particles. Uncontrolled fibrillation must be prevented to insure good quality production from the powder. Premature fibrillation leads to the formation of lumps which cannot be broken up easily. 

Figure 21b shows the change of resin temperature in mold with time after the injection [Okamoto et al., 1995]. Here, the resin temperature was measured by embedding a thermocouple in the mold set at 95°C. When the melt is out of the shear field in the mold, the spinodal temperature will drop to the static one (T = 223°C) and, for about 4 s after injection, the blends is in the two-phase region. The phase separation with large diffusion coefficient, D, will proceed until the melt cools down to T. Then, at T < T, the phase dissolution takes place. The dissolution slows down near T... 

A low shear heat screw is recommended, with L/D = 18 to 22 and a compression ratio from 2.0 to 2.6. The screw should be protected against corrosion and wear, by either plating or nitrating. If any scratch is observed on the surface of the barrel, screw, or nozzle, it must be repaired immediately, otherwise owing to resin retention, it may cause burn marks or black spots on the moldings. The resin temperature may be checked with a few air shots. Due to thermal degradation, temperatures above 210°C may cause burn marks, black spots or mold-rust. 

This will generally occur by boosting mold and/or resin temperature to decrease cure time while remaining subject to temperature requirements. For epoxy + AEP in 0.A76 cm cavity, a mold temperature of 125°C and a resin temperature of 70 C will provide a demold time of about 45 sec and a peak temperature of 262°C. In a 0.635 cm cavity the same material will process best on the basis of minimum demold time and avoidance of thermal degradation with a mold temperature of 115°C and a resin temperature of 55°C. 

The above results suggest that the behavior of asphaltenes in solutions is governed by some sort of aggregation equilibrium. Many factors such as the nature of solvent, the concentration of asphaltenes or resins, temperature, and so on, can influence the level of aggregation. 

Rough wavy surface (applesauce) wrong resin/temperature too low or high. 

The extraction of uranium from sea water with the AN-DVB-AO resin was carried out by column method under the condition as follows resin 5g, flow rate of natural sea water 20 ml/min-g-resin, temperature 25 2°C. 

In usual RTM applications, the resin is kept in the reservoir of the injector at room temperature, and the mold is heated for the cross-linking chemical reaction of the resin. In an ideal injector, the resin storage tank and the connection tubes should be heated to keep the resin at a desired temperature (usually at the same temperature of the mold), otherwise the resin temperature may vary due to the heat transfer between the mold and the resin as it propagates. For example, the heater jacket around the resin cylinder in Fig. 9.16a allows one to control the resin temperature up to 175°C. Additional heater jackets or insulator jackets are placed around the inlet tubes between the injector and the mold... 

Pultrusion. in pultmsion a combination of liquid resin and continuous fiber is pulled continuously through a heated die of the required shape for continuous profiles, such as structural channel, angles, rods, and sheets (1). The plastic sides and top of stepladders are common examples of pultrusion. Commonly employed resins are polyesters, epoxies, and polyurethanes. A typical process might be 3-5 min in duration where resin temperatures ramp rapidly from ambient to temperatures in excess of 150°C, hold for a short time, and ramp back down (see Fig. 10). 

Fig. 18. The calorimctricaljy determined relative internal energy contributions as a function of elongation 1, 2, 3, 4 — network with 15% of a multifunctional crosslinking resin 5, 6 — network with 45% of a multifunctional resin. Temperatures 1 — 20°, 2 — 30°, 3 — 50°, 4 — 70° and 100 °C 5 — 20°, 6 — 80 °C. The dotted line represents intramolecular (conformationaO energy contribution for PDES...

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