Macromolecules Article a) a) es CHa 。 b) b) CBO-P-OC N-g广ow cc品c2 7h 销室销 6% G) ceeHao 64 d) e程 d) 40 品8 e“ae 2 16011201000020 e2()P,间D2同p, show proportion of phosphorus ashigh as 8ct0eo2.a2T respectively. Moreover, the char layers of EP1-DDM and EP2- DDM are extremely dense, as shown in Figure 7b. Besides, as shown in Table 2, a large proportion of phosphorus as high as ∼53.5% was remained in the char, which suggests that the degradation of phosphorus-containing groups produced phosphate structure in the condensed phase and promoted Figure 2. 1 H NMR spectra of (a) DP1, (b) DP2, (c) EP1, and (d) EP2. Figure 3. 13C NMR spectra of (a) DP1, (b) DP2, (c) EP1, and (d) EP2. Macromolecules Article DOI: 10.1021/acs.macromol.7b00097 Macromolecules 2017, 50, 1892−1901 1896