I already posted this question 2rd time now someone didn\'t answer the whole thi

Question

I already posted this question 2rd time now someone didn't answer the whole thing this is a 2rd refund please just answer all parts:

You are required to answer all parts of the question. Our professor gave it as you see it as a single question, so to save to getting a refund and posting again just please.

I know the rule is 1 question at a time in material science at our university this is a single question!!

And correctly clear writting please.

it would be a pain for me to separate them, since I have a fair bit of them.

And finally please do not write on a piece of paper then take a single photo with your mobile phone its going to be blured we can't see it use a photo copier. otherwise take multiple close up photos if mobile is all you have.

2. a) WW hat types of polymers can crystal (1 mark) ise? b) What factors affect the degree of crystallinity? (3 marks) t is the effect of increased crystallinity on density, strength, toughness and heat resistance. (4 marks) c) sketch a typical stress versus strain plou for a semicrystalline polymer above its glass transition temperature, markinge on your sketch where you would expect necking to occur. Explain the relationship between necking and the molecular deforma tion that has occurred. (6 marks) i) Explain the trends you see for change of strength and failure strain with increased strain rate for such a polymer- (8 marks) c> Using Figure 1 below. state which curve best describes the behaviour of CiD an amorphous lincar polymer Temperature (ii) a lightly cross linked polymer 1.5O 250 3Soal (iii) a highly crystalline polymer 1OG CivD a heavily crossed. linked polymer los 102 1 O 1 SO Temperature Figure 1 ASO 1O3 lo 1O 10-2

Explanation / Answer

(a) polymer which has parallel chains and chain packed closely together and a wella s overlapping and aligning the atoms of the molecules ina repeating lattice structure can crystallise.

(b)factors affecting the degree of crystallinity are(i)rate of cooling,(ii)chain configuration,(iii)linear/branched polymer(iv)degree of polymerisation.

(C) if the degree of crystallinity increases then tensile stress will be high,lower toughness as elongation to rupture,heat resistance will be lower.

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