The glass transition temperature of PS and PB are 95 °C and -90 °C, respectively. What is the glass transition of 50 wt% PS - 50 wt.% PB of immiscible polymer blend?
The glass transition temperature of PS and PB are 95 °C and -90 °C, respectively. What is the gla...
How to determine the glass transition temperature of a polymer? What factors will affect the glass transition temperature?
Which of the following amorphous plastics has the highest glass-transition temperature? a. PE b. PVC c. PS d. PP
(2 points). Is it possible for a polymer to have both a glass transition temperature, Tg, and a melting temperature, Tm? How is this explained thermodynamically?
1. Below is the phase diagram of Pb-Sn alloy. (a) Describe what happens to a 20%-Pb 80%-Sn alloy as temperature decreases from 300 °C to 50 °C; use sketches as needed. (b) When temperature is kept constant at 200 °C, describe what happens as the Sn concentration is increased from 10 wt% to 90 wt%; use sketches as needed. 100% Liquid Procutectic α 24% Eutectic α Liquid 76% Eutectic β Alloy I Alloy 2 Liquid 49% 327 Liquidus 300 Liquid...
(9a) What material type has a glass transition temperature (Tg)? (9b) How do the material properties differ below and above the glass transition temperature (Tg)? (9c) What material type has a melting temperature only and no Tg?
Question 2. a) What is the distinction between glass transition temperature and melting temperature? (Perhaps use a sketch to explain) b) Relating to the previous question (and sketch?) explain why glass may be drawn into fibres, whereas crystalline alumina may not c) Borosilicate glasses and fused silica exhibit higher resistance to thermal shock, to some ofthe more day-to-day glasses and ceramics. Why is this so? End of Tutorial Questions
High density polyethylene (HDPE) has a glass transition temperature below 0 C. However, HDPE appears as plastic rather than a rubbery material at room temperature. Why? (Max 100 words) (5 Points) Enter your answer What is the glass state? What is the glass transition temperature? (Max 100 words) (5 Points) ) Enter your answer Why polymers do not want to mix? (Consider the entropy and enthalpy effects, and compare to small molecular compounds.) (Max 100 words) (5 Points) Enter your...
Composition (at% Pb) 20 30 40 70 100 1200 a М MeәРЫ +L Temperature (°C) Temperature (°F) Mg2Pb a + Mg Pb B + Mg, Pb 200 Mg2Pb 40 60 100 (Mg) Composition (wt% Pb) (Pb) (10 minutes) Use the above Magnesium (Mg) - Lead (Pb) phase diagram. A 30%Pb - 70%Mg alloy is slowly cooled from 700°C to 300°C. Answer the following questions and don't forget the units. (A) At what temperature does the first solid phase form? (B)...
1. What do we mean by thermoplastic polymer? 2. What is the definition of thermosetting polymer? 3. What is glass transition temperature (as it relates to polymers)? 4. What is the meaning of crosslinking as it relates to polymers? a) In terms of tensile strength, melting point etc. how does a crosslinked polymer compare with a non-crosslinked polymer? b) Draw a simple schematic diagram of linear polyethylene and crosslinked polyethylene (chemical structure of ethylene is CH2 = CH2).
Question 4 The following figures and tabulated data were obtained during the Phase diagram experiment for Pb-Sn using DSC machine. Tables 1-4 shows the wt% composition of Sn in Pb at 1) Use figures 1 and 2, and Table 1 to plot the Temperature 2) Use the figures 1 and 2, and Table 2 to plot the different temperatures (°C) against wt% composition of Sn in Pb Temperature (°C) against wt% composition of Sn in Pb on the same graph...