Fall_2006_Exam_1 - POLYMER PROCESSING - FALL 2006 EMA 4666C...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
POLYMER PROCESSING - FALL 2006 NAME: PUT ON LAST PAGE and SIGN HONOR CODE EMA 4666C – EXAM 1 STUDENT #:______________________ INSTRUCTIONS: Read the entire exam carefully . Answer every question to the best of your ability, based upon the available information. State all assumptions in answers. SECTION I: Polymer Structures/Properties. (2 pts each/12 pts total) 1. Draw the structural repeat units for the following polymers. 2. Indicate the type of polymerization process used to synthesize each of the structures, i.e. condensation, addition, ring opening. 3. State the relative Tg and/or Tm for each polymer. If a Tm is not expected indicate by NA. Polymer Structural Repeat Unit Process Tg Tm 1. poly(ethylene) 2. poly(arylene ether sulfone) 3. poly(hexamethylene) (Nylon 6,6) 4. poly(vinyl-n-methyl ether) 5. poly(styrene) 6. poly(phenylene adipamide) “Kevlar”
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Student Number:___________________________ Concepts. (2pts ea/12pts total) Answer the following statements with TRUE or FALSE . If the statement is false, state the reason(s). If you believe a statement can be made TRUE by a simple qualifier, then state it clearly. HINT: Normally one word can be modified to correct false statements. 7. A higher cooling rate decreases the specific volume of a glassy polymer such as polystyrene above the Tg. 8. The elastic modulus, measured in the machine direction, of an injection molded semi- crystalline polymer is directly proportional to the volume fraction of crystalline material in spherulites. 9. Annealing an amorphous polymer, such as polycarbonate, at ca. 10 degrees below the glass transition temperature decreases the post yield stress drop and elongation to failure. 10. Plastic (viscous) flow in a stress – strain experiment decreases as the Mz value of the polymer increases. 11. A shish-ka-bob morphology is created by using a counter-rotating die configuration to extrude rigid polymer. 12. The rubber modulus slope of the Storage modulus is positive for a high molecular weight, linear polymer. EMA 4666C Fall 2006 Exam 1 2
Background image of page 2
Student Number:___________________________ Graphical Relationships: A. SHOW ALL EQUATIONS. B. EACH GRAPH SHOULD BE A LINEAR RELATIONSHIP. C. LABEL ALL AXES WITH THE APPROPRIATE UNITS. D. CLEARLY STATE ALL ASSUMPTIONS. 13. Sketch the general features of the storage modulus (E’) a function of temperature for poly(styrene-block-butadiene-block-styrene) copolymer. Label the major transition (s) and their magnitude relative to E’ 3 pts 14.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 13

Fall_2006_Exam_1 - POLYMER PROCESSING - FALL 2006 EMA 4666C...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online