Equimolar mixture of terephthalic acid and butylene glycol was taken to synthesize a polyester. The reaction was stopped at $99.6 \%$ conversion of the acid monomer. The weight-average molecular weight ( $\bar{M}_{w}$) of the synthesized polyester is $\_\_\_\_$ $\mathrm{g} / \mathrm{mol}$ (rounded off to the nearest integer).
