of the exotherm. The melting temperatures obtained during the second heating
cycle were considered in order to ensure identical thermal histories of the
investigated copolymers.
The CRYSTAF analysis of the 1-octene and the 1-octadecene copolymers is
shown in Fig. 2.40. Copolymers with higher comonomer contents (e.g. entries 8.2
and 18.11) partially crystallize at temperatures lower than 30
C. This is not
relevant in the current study because only the peak maximum temperatures are
used in the discussion.
2.2.3.5 Discussion and Evaluation
The dependence of the melting temperature determined by DSC follows the
expected linear relationship according to the Flory–Huggins theory. As expected,
the nature of the comonomer does not influence the melting point depression.
Figure 2.41a demonstrates the melting points of all synthesized propylene/α-olefin
Fig. 2.41 Melting temperature T m (a) and crystallization temperature T c (melt) (b) as a function
of copolymer composition, determined by DSC (reprinted from [110] with permission of WileyVCH)
Fig. 2.40 CRYSTAF analysis of metallocene-catalysed propylene-α-olefin copolymers, comonomer 1-octene (a), comonomer 1-octadecene (b) (reprinted from [110] with permission of WileyVCH)
2.2 Crystallization Analysis Fractionation
63
cycle were considered in order to ensure identical thermal histories of the
investigated copolymers.
The CRYSTAF analysis of the 1-octene and the 1-octadecene copolymers is
shown in Fig. 2.40. Copolymers with higher comonomer contents (e.g. entries 8.2
and 18.11) partially crystallize at temperatures lower than 30
C. This is not
relevant in the current study because only the peak maximum temperatures are
used in the discussion.
2.2.3.5 Discussion and Evaluation
The dependence of the melting temperature determined by DSC follows the
expected linear relationship according to the Flory–Huggins theory. As expected,
the nature of the comonomer does not influence the melting point depression.
Figure 2.41a demonstrates the melting points of all synthesized propylene/α-olefin
Fig. 2.41 Melting temperature T m (a) and crystallization temperature T c (melt) (b) as a function
of copolymer composition, determined by DSC (reprinted from [110] with permission of WileyVCH)
Fig. 2.40 CRYSTAF analysis of metallocene-catalysed propylene-α-olefin copolymers, comonomer 1-octene (a), comonomer 1-octadecene (b) (reprinted from [110] with permission of WileyVCH)
2.2 Crystallization Analysis Fractionation
63