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Lignophenol (LP)-graft-poly(2-ethyl-2-oxazoline) (POZO) was prepared to reuse lignin, an industrial waste material, and to produce novel LP-based polymer blends with poly(vinyl chloride) (PVC), poly(bisphenol A carbonate) (PC), polyvinylpyrrolidone (PVP), and polystyrene (PSt) as commodity polymers. The resulting graft polymer was soluble in various types of organic solvents such as chloroform, THF, acetone, and methanol, unlike LP. The miscibility of LP-graft-POZO with commodity polymers was measured by differential scanning calorimetry (DSC) to determine the glass transition temperatures (T g ). In the cases of the blends of LP-graft-POZO with PVC, PC, and PVP, the T g values decreased during the second scan. Moreover, in the cases of the blends with PVC and PVP, the T g values were not detected during the third scan. Therefore, it was inferred that LP-graft-POZO was miscible with PVC, PC, and PVP while forming single phases; in particular, the blends of LP-graft-POZO with PVC and PVP exhibited a secondary miscibility because the T g values were not detected. Furthermore, the blend of LP-graft-POZO with PC exhibited better thermostability than LP and LP-graft-POZO. These results indicated that LP blended with POZO could be used as a polymer additive and as an adhesive to combine different polymers, organic-inorganic polymers, etc.

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We report the direct synthesis of new functional novolacs having allyl ether (4) or bromoalkyl groups (5 and 6) in the side chain by the addition-condensation of allyl phenyl ether (1), 1-bromo-2-phenoxyethane (2) or 1-bromo-4-phenoxybutane (3) with formaldehyde. The structure of these novolacs was confirmed by Fourier transform infrared, 1 H NMR and 13 C NMR spectra. The number-average molecular weights (M n ) of the obtained polymers were found to be B1000-3000. In the case of the polymerization of 1 with formaldehyde using hydrated sulfuric acid as a catalyst, Claisen condensation did not occur with the polymerization; therefore, pure allylated novolac (4) without a phenol moiety was obtained. Thus, in this process, phenolformaldehyde condensation proceeded under such conditions that the functional group was not affected. These polymers (4-6) have considerable potential as reactive polymers in the field of materials science. Their applications are as follows: (i) a key reaction of a latent curing system: thermal stimuli-induced Claisen rearrangement of allylated novolac to generate phenolic hydroxyl groups; (ii) vinyl ether-modified novolac (7) prepared by 1-bromoethoxy-group-modified novolac; and (iii) an amphiphilic graft-shaped polymer prepared by bromoalkyl-group-modified novolac-initiated ring-opening polymerization of 2-methyl-2-oxazoline. Polymer Journal ( Keywords: allyl phenyl ether; Claisen condensation; graft polymerization; novolac; phenolic resin; polycondensation; polymer reaction INTRODUCTION Phenolic resins 1-10 and related polymers 11-22 are a very important class of common organic polymers, and have numerous applications in the development of materials 1-6 such as thermosetting resins, adhesives, photoresists and polymer composites. The main characteristics of phenolic resins, such as heat stability and mechanical properties, are attributed to their rigid rod-like polymer backbone of poly(phenylenemethylene). 2,23 From this viewpoint, we have synthesized a wide variety of aromatic polymers from alkoxylated phenol derivatives such as anisole, phenethol and diphenyl ether by a method similar to acid-catalyzed phenol-formaldehyde condensation. 2,[23][24][25][26][27][28][29][30][31][32][33] The obtained polymers exhibit good solubility in organic solvents and they are more resistant to heat and oxidation than are phenolic novolacs. Furthermore, using hydroxyl-group-functionalized phenol derivatives, a functional novolac can be prepared by a one-step procedure. Therefore, a desired polymer can be designed using this methodology (Figure 1). It is very important to extend the use of this methodology to a wide variety of applications in the field of materials science.Reactive polymers have attracted considerable interest in the field of materials science because their characteristics and functions can be enhanced to develop crosslinking agents, resist materials, expandable

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