NOVELTY - Manufacturing polycarbonate involves combining methane and inlet water; converting obtained methanol to propylene, gasoline aromatics, and gasoline olefins; converting the propylene and gasoline olefins to hydrogen, first benzene, and toluene; reacting the first benzene with propylene; reacting obtained cumene with oxygen; cleaving obtained cumene hydroperoxide; reacting the obtained phenol and acetone; and reacting obtained dihydric aromatic compound with a carbonate precursor.    USE - For manufacture of polycarbonate (claimed).    ADVANTAGE - The method reduces cost of feedstocks; enables an effective utilization of an untapped resource; reduces demand for a commodity which is currently very expensive e.g. crude oil; increases availability of materials such as benzene; saves production of benzene from methanol by enabling the used of side products from some intermediate steps to be recycled as feed stock into later intermediatary steps and/or for use in factory. The production of benzene enables the conservation of material and thus reduces costs and waste products.    DETAILED DESCRIPTION - Manufacture (m1) of polycarbonate involves    (A) combining methane and inlet water to produce methanol;    (B) converting the methanol to propylene, gasoline aromatics, and gasoline olefins;    (C) converting the propylene and gasoline olefins to hydrogen, first benzene, and toluene;    (D) reacting the first benzene with propylene to form cumene;    (E) reacting the cumene with oxygen to form cumene hydroperoxide;    (F) cleaving the cumene hydroperoxide to produce acetone and phenol;    (G) reacting the phenol and acetone to produce a dihydric aromatic compound; and    (H) reacting the dihydric aromatic compound with a carbonate precursor.    INDEPENDENT CLAIMS are included for:    (1) method (m2) for the manufacture of polyetherimide involving a) carrying out steps (A) - (G); b) reacting the dihydric aromatic compound with a base to form a dihydric aromatic salt; and c) reacting the dihydric aromatic salt with a material to form the polyetherimide; and    (2) manufacturing (m3) cumene involving carrying out steps (A) - (D).