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5 Polyamides
Polyamides are the class of the polymers with repeating and interlinked structural
amide linkages (-NH-CO-). Nylon™ having integral amide groups is one of the
families of polyamide materials [25–27]. Nylon™ is generally referred to as
synthetic polyamide materials synthesized using the aliphatic monomers [28–31].
Generally, the polymers obtained via condensation reaction of diacids and diamines
are referred to as AABB-type, and from lactams, it is referred to as AB-type as
shown in Fig. 9. There are many synthetic techniques employed for the synthesis of
polyamides, and two fundamental processes are used to obtain the desired polyamide
material: one method is polycondensation of diacids and diamines, and the other is
ring-opening polymerization of the lactam ring such as caprolactam (Fig. 10)
[32, 33].
There are various types of nylons, and the associated number tells us the type of
Nylon™, for example, Nylon 66 or polyamide 66 (PA 66). Number suffixing
Fig. 6 Biosynthesis of PHBV
Fig. 7 Structure of PHBHHxPHBHH x is produced on similar fermentation methods as other
PHAs like PHB and PHBV. The substrates are bio-based generated aliphatic fatty acid and soybean
oil. Apart from this, it can also be prepared in agricultural crops, which is a cheaper process as
compared to bacterial fermentation. A variety of plants can be used, such as corn, sugarcane, and
switch grass. The process PHBHH x goes through various modifications in biosynthetic pathways
of fatty acids and amino acids (in plastids and peroxisome) in different compartments of a cell
(Fig. 8).
M. A. Ali et al.
5 Polyamides
Polyamides are the class of the polymers with repeating and interlinked structural
amide linkages (-NH-CO-). Nylon™ having integral amide groups is one of the
families of polyamide materials [25–27]. Nylon™ is generally referred to as
synthetic polyamide materials synthesized using the aliphatic monomers [28–31].
Generally, the polymers obtained via condensation reaction of diacids and diamines
are referred to as AABB-type, and from lactams, it is referred to as AB-type as
shown in Fig. 9. There are many synthetic techniques employed for the synthesis of
polyamides, and two fundamental processes are used to obtain the desired polyamide
material: one method is polycondensation of diacids and diamines, and the other is
ring-opening polymerization of the lactam ring such as caprolactam (Fig. 10)
[32, 33].
There are various types of nylons, and the associated number tells us the type of
Nylon™, for example, Nylon 66 or polyamide 66 (PA 66). Number suffixing
Fig. 6 Biosynthesis of PHBV
Fig. 7 Structure of PHBHHxPHBHH x is produced on similar fermentation methods as other
PHAs like PHB and PHBV. The substrates are bio-based generated aliphatic fatty acid and soybean
oil. Apart from this, it can also be prepared in agricultural crops, which is a cheaper process as
compared to bacterial fermentation. A variety of plants can be used, such as corn, sugarcane, and
switch grass. The process PHBHH x goes through various modifications in biosynthetic pathways
of fatty acids and amino acids (in plastids and peroxisome) in different compartments of a cell
(Fig. 8).
M. A. Ali et al.