PEPERIKSAAN IJAZAH SARJANA MUDA SAINS
EXAMINATION FOR THE DEGREE OF BACHELOR OF SCIENCE
SESI AKADEMIK 2016/2017 : SEMESTER 1 ACADEMIC SESSION 2016/2017 : SEMESTER 1
SID2002 : KIMIA POLIMER INDUSTRI I
INDUSTRIAL POLYMER CHEMISTRY I
Dis 2016/ Jan 2017 MASA : 2 jam
Dec 2016/ Jan 2017 TIME : 2 hours
ARAHAN KEPADA CALON : INSTRUCTIONS TO CANDIDATES :
Kertas soalan ini mengandungi Bahagian A dan B.
This paper consists of Section A and B.
Jawab soalan mengikut arahan yang diberikan dalam setiap bahagian.
Answer the questions according to the instructions given in each section.
(Kertas soalan ini mengandungi 4 soalan dalam 7 halaman yang dicetak) (This question paper consists of 4 questions on 7 printed pages)
2/7 BAHAGIAN A (50 MARKAH)
SECTION A (50 MARKS)
Jawab semua soalan daripada bahagian ini.
Answer all questions from this section.
1. Polimer Z dilarutkan dalam xylena dan masa aliran larutan polimer pada kepekatan yang berbeza diukur menggunakan meter kelikatan Ubbelohde. Diberi masa aliran xylene, to = 125 s.
Polymer X was dissolved in xylene and the flow time of the polymer solution at different concentration was measured using Ubbelohde viscometer. Given the flow time of xylene, to = 125 s.
Jadual 1 : Aliran masa larutan Polimer Z dengan kepekatan berbeza Table 1: Flow time of Polymer Z solution at various concentrations
Kepekatan larutan polimer X / (mol dm-3) Concentration of polymer X solution / (mol dm-3)
Aliran masa, t / (s) Flow time, t / (s)
0.2716 359.8
0.1940 278.2
0.1509 237.9
0.1235 212.8
0.1045 196.4
(a) Ukuran menggunakan meter kelikatan Ubbelohde perlu diambil pada suhu yang malar untuk mendapatkan keputusan yang tepat. Jelaskan bagaimana suhu mempengaruhi analisis tersebut.
The measurements using Ubbelohde viscometer need to be conducted in water bath at constant temperature in order to obtain accurate results. Explain how temperature influences the analysis.
(4 markah/marks)
(b) Berdasarkan data yang diberikan dalam Jadual 1:
Based on the data given in Table 1:
(i) Bina sebuah jadual yang menunjukkan kelikatan “inherent” (ηinh) dan kelikatan “reduced” (ηred) pada setiap kepekatan. Tunjukkan jalan kerja yang berkenaan.
Construct a table of inherent viscosity (ηinh) and reduced viscosity (ηred) of the solution for each concentration. Show the working where relevant.
(6 markah/marks)
3/7 (ii) Plot graf yang sesuai menggunakan nilai ηinh dan ηred pada paksi yang sama untuk mendapatkan nilai kelikatan intrinsik bagi larutan polimer tersebut.
Plot relevant graphs using ηinh and ηred on the same axis to obtain the intrinsic viscosity, η of the solution.
(8 markah/marks)
(iii) Tentukan kelikatan molekul berat purata (Mv) bagi polimer tersebut dengan menggunakan persamaan Mark-Houwink. Diberi pemalar dalam persamaan tersebut, K = 5.1 x 10-3 cm3 g-1 dan a = 0.55.
Determine viscosity average molecular weight, Mv of the polymer using Mark-Houwink equation. Given the constant in Mark-Houwink equation, K
= 5.1 x 10-3 cm3 g-1 and a = 0.55.
(3 markah/marks)
(c) Persamaan Mark-Houwink menunjukkan bahawa kelikatan polimer berkait-rapat dengan berat molekul polimer. Terangkan bagaimana berat molekul polimer pengaruh berat kelikatan
Mark-Houwink equation shows that viscosity and molecular weight of polymers are related to each other. Explain how molecular weight of polymer influences its viscosity.
(4 markah/marks)
2. (a) Jelas dan bezakan pempolimeran pukal dan pempolimeran larutan.
Jawapan anda hendaklah turut menjelaskan kelebihan dan kekurangan setiap teknik.
Describe and compare bulk polymerization and solution polymerization. Your discussion must include the advantages and disadvantages of each.
(12 markah/marks)
(b) Polietilena tereftalat (PET) biasanya digunakan untuk membuat botol air, bekas makanan, dan pembalut makanan. Cadang dan jelaskan mana di antara dua teknik di 2(a) lebih sesuai digunakan untuk menghasilkan PET.
Polyethylene terephthalate (PET) is commonly used to produce water bottles, food containers, and food wrapper. Suggest and explain which of the two techniques in 2(a) is more suitable to be used to produce PET.
(5 markah/marks)
4/7 (c) Salah satu masalah yang dihadapi di kebanyakan negara ialah masalah kekurangan tapak pelupusan sampah. Banyak industri, terutamanya industri pembungkusan telah menggantikan plastik pembungkus yang konvensional kepada plastik terbiodegradasi bagi mengatasi masalah tersebut. Jelaskan:
One of the problems faced in many countries is the scarcity of landfill area. Many industries, especially the packaging industries have replaced their conventional plastics to biodegradable plastics to help to address the problem. Explain:
(i) Bagaimana plastik terbiodegradasi membantu mengurangkan masalah kekurangan tapak pelupusan sampah?
How does having biodegradable plastic help to reduce scarcity of landfill area?
(2 markah/marks)
(ii) Sesetengah plastik terbiodegradasi tidak terurai di tapak pelupusan sampah. Jelaskan faktor-faktor yang boleh mempengaruhi penguraian plastik tersebut.
Some of the “biodegradable” plastics do not decompose well in the landfill area. Discuss the factors that affect biodegradation of the plastics.
(6 markah/marks)
5/7 BAHAGIAN B (50 MARKAH)
SECTION B (50 MARKS)
Jawab SEMUA soalan.
Answer ALL questions.
3. Jawapan BETUL atau SALAH dan berikan alasan anda.
Answer TRUE or FALSE and give your reason.
(a) Dalam makmal, DRC susu getah pekat ditentukan menggunakan asid formik.
In the laboratory, DRC of concentrated latex is determined using formic acid.
(b) SMR 10 mempunyai kandungan jirim meruap yang rendah berbanding SMR 20.
SMR 10 has low content of volatile matter compared to SMR 20.
(c) Penyahprotein getah asli akan meningkatkan rayapan dan pengenduran tegasan getah.
Deproteinized natural rubber will increase the creep and stress relaxation of rubber.
(d) Cerun awal pada lengkungan tegasan-terikan memberikan ukuran keliatan.
The initial slope of stress-strain curve gives a measure of toughness.
(8 markah/marks)
4. Berikan penerangan ringkas mengenai berikut:
Give brief explanations of the following:
(a) Senarai TIGA aplikasi utama dan nyatakan teknik umum yang terlibat bagi
pemprosesan produk susu getah.
List THREE main applications and indicate the general techniques involved in the processing of latex products.
(6 markah/marks)
(b) Terangkan prosedur bagi ujian DRC.
Describe the procedure for DRC test.
(4 markah/marks)
6/7 (c) Bandingkan sifat rayap bahan likatelastik dengan bahan likat tulin dan
elastik tulin melalui lakaran graf.
Compare the creep behaviour of the viscoelastic material with the pure viscous and the pure elastic materials by sketching graphs.
(5 markah/marks)
(d) Satu sampel polimer 50 cm panjang, 1.0 cm lebar dan 0.1 cm tebal telah dikenakan daya 20 N. Jika ia diregangkan kepada 50.5 cm panjang, apakah ‘Young’s modulus’ dalam pascal?
A sample of polymer 50 cm in length, 1.0 cm in width and 0.1 cm in thickness was subjected to a force of 20 N. If it is stretched to 50.5 cm long, what is its Young’s modulus in pascal?
(5 markah/marks)
(e) Senaraikan keperluan molekul bagi suatu bahan untuk mempamerkan sifat keanjalan getah.
List the molecular requirements for a material to exhibit rubber elasticity
behaviour.
(3 markah/marks)
(f) Bandingkan proses pembekuan getah asli untuk tindak balas lambat dan tindak balas cepat. Huraikan mekanisme yang terlibat semasa tindak balas cepat tersebut.
Compare the coagulation process of natural rubber for the slow reaction and fast reaction. Explain the mechanisms involved during the fast reaction.
(7 markah/marks)
(g) Berikan TIGA bahan penyebatian utama getah dan nyatakan fungsi mereka.
Provide THREE major rubber compounding ingredients and indicate their
function.
(6 markah/marks)
7/7 (h) Tulis nota pendek bagi DUA istilah berikut:
Write short notes on TWO of the following terms:
(i) Pengenduran tegasan Stress relaxation
(ii) Ujian kealkalian Alkalinity test
(iii) Suhu peralihan kaca Glass transition temperature
(6 markah/marks)
TAMAT END
