Question 27 (Textile Engineering & Fibre Science)
Consider the fibres in Group I and the corresponding monomer(s) in Group II. Choose the correct combination from amongst A, B, C and D
| Group I | Group II | ||
| P | Polyester (PET) | 1 | CH2=CH.CN, CH2=CH,COOCH3 |
| Q | Nylon 6 | 2 | HO-(CH2)2-OH, HOOC*****COOH |
| R | Nylon 6,6 | 3 | HOOC-(CH2)6-COOH, H2N-(CH2)6-NH2 |
| S | Acrylic | 4 | HO-(CH2)4-OH, HOOC*****COOH |
| 5 | HOOC-(CH2)4-COOH, H2N-(CH2)6-NH2 | ||
| 6 | H2N-(CH2)5-COOH |
| (A) | P-4, Q-1, R-5, S-3 |
| (B) | P-2, Q-6, R-5, S-1 |
| (C) | P-2, Q-6, R-3, S-4 |
| (D) | P-3, Q-2, R-5, S-1 |
[Show Answer]
Option B is correct
Frequently Asked Questions | FAQs
What is the formula for polyester?
The formula for polyester is typically represented as (C10H8O4)n, where n represents the number of repeating units in the polymer chain. This formula represents a general structure for polyester, and there are various types of polyesters with different repeating units and molecular structures.
Polyester is a synthetic polymer that is formed by the condensation reaction between dicarboxylic acids (or their derivatives) and diols. The most commonly used dicarboxylic acid in polyester production is terephthalic acid (C6H4(CO2H)2), and the commonly used diol is ethylene glycol (HOCH2CH2OH). The reaction between terephthalic acid and ethylene glycol forms polyethylene terephthalate (PET), which is a widely used polyester.
The chemical reaction can be represented as follows:
HOOC-C6H4-COOH + HOCH2CH2OH → HOOC-C6H4-CO-OCH2CH2-OH + H2O
In this reaction, the carboxyl groups (COOH) of the acid react with the hydroxyl groups (OH) of the diol, resulting in the formation of ester linkages (CO-O) and the release of water (H2O). This process is known as esterification.
The reaction continues to repeat, forming a long polymer chain with repeating units of terephthalate and ethylene glycol. The value of n in the polyester formula represents the number of repeating units, and it determines the molecular weight and properties of the polyester.
Polyester is widely used in various applications, including textile fibers, films, bottles, packaging materials, and more, due to its excellent strength, durability, wrinkle resistance, and moisture-wicking properties.
What is the structure of nylon 6?
Nylon 6, also known as polyamide 6 (PA 6), is a synthetic polymer that belongs to the family of polyamides. The structure of nylon 6 is derived from the polymerization of a monomer called caprolactam. The repeating unit in nylon 6 is derived from caprolactam and consists of six carbon atoms.
The structural formula of nylon 6 can be represented as follows:
[-CH2-(CH2)4-CO-]n
In this structure, the “-CH2-” unit represents a methylene group, and the “-CO-” unit represents a carbonyl group. The (CH2)4 segment indicates a chain of four methylene units, which connects the carbonyl groups.
During the polymerization process, caprolactam undergoes a ring-opening polymerization reaction, where the cyclic structure of caprolactam opens up, and the monomer units link together to form a long polymer chain. This reaction results in the formation of nylon 6 with repeating units of (-CH2-(CH2)4-CO-) in the chain.
The structure of nylon 6 provides it with desirable properties such as high strength, toughness, abrasion resistance, and chemical resistance. Nylon 6 is commonly used in various applications, including textile fibers, engineering plastics, automotive components, industrial materials, and more.
What is the structural formula of nylon 6?
The structural formula of nylon 6, also known as polyamide 6 (PA 6), can be represented as follows:
H2N-(CH2)5-CO-(NH-(CH2)4-CO)n-H
In this formula, the “-NH-” represents an amino group (NH2), the “-CO-” represents a carbonyl group (C=O), and the (CH2)5 and (CH2)4 segments indicate chains of five and four methylene units, respectively. The “-H” at both ends of the formula represents hydrogen atoms.
This structural formula represents the repeating unit of nylon 6, which is derived from the polymerization of the monomer caprolactam. Nylon 6 is formed through a ring-opening polymerization reaction of caprolactam, where the cyclic structure of caprolactam opens up, and the monomer units link together to form a long polymer chain with repeating units of (-NH-(CH2)5-CO-(NH-(CH2)4-CO-)).
Nylon 6 possesses excellent mechanical strength, abrasion resistance, and chemical resistance, making it suitable for various applications, including textile fibers, engineering plastics, films, and industrial components.
What is the structure of acrylic?
Acrylic is not a specific compound but rather a term commonly used to refer to a group of synthetic polymers that are derived from acrylic acid or its esters. Acrylic polymers are typically derived from the monomer methyl methacrylate (MMA), which is the most widely used acrylic monomer.
The structural formula of methyl methacrylate (MMA) is as follows:
CH2=C(CH3)COOCH3
In this formula, the “CH2=C” represents the vinyl group, “CH3” represents a methyl group, and “COOCH3” represents the ester group. The vinyl group consists of two carbon atoms connected by a double bond.
Methyl methacrylate (MMA) is polymerized to form polymethyl methacrylate (PMMA), which is commonly known as acrylic. PMMA is a transparent, rigid, and durable thermoplastic material. It is often used as a substitute for glass due to its high optical clarity and impact resistance. PMMA is widely used in applications such as signs, displays, lighting fixtures, automotive parts, and medical devices.
It’s important to note that acrylic can also refer to other types of acrylic polymers that are derived from other acrylic monomers, such as ethyl acrylate or butyl acrylate. These acrylic polymers have similar structures but differ in the side chains attached to the main polymer backbone.