| 摘要 |
FIELD: chemistry.SUBSTANCE: invention relates to method for acetone and phenol determination in equilibrium gas phase over polymer materials and in air of the working zone. Proposed method consists in using an array of 2 piezoelectric quartz resonators with intrinsic oscillation frequency of 10 MHz, wherein electrodes are modified by coating them with separate solutions of polyethylene glycol sebacate (PEGSb) and trioctyl phosphine oxide (TOPhO), wherein modifiers are applied so that after solvent removal by drying in drying chamber at temperature of 40-50 °C for 15-20 min weight of film of each sorbent is 15-20 mcg. Modified piezoelectric quartz resonators are placed into closed detection cell of gas analyser and held therein for 5 min to achieve stable zero signal; then 5.00 g sample of finely ground phenol formaldehyde resin is placed into sampler, tightly closed by plug, and held at 20±1 °C for 15 min, then 3 cmof equilibrium gas phase is taken through plug using syringe and injected into closed detection cell of gas analyser; changes of piezo sensor oscillation frequency are recorded during 120 s, and analytical signals are registered as maximum oscillation frequency change of each sensor for 120 s (ΔF). Ratio of analytical signals of 2 piezoelectric quartz resonators is calculated as sorption efficiency parameter A(PEGSb/TOPhO)=ΔF/ ΔF, ratio of current responses (ΔF) at 5 and 120 s of sorption is calculated as kinetic coefficient γ=ΔF/ ΔFfor piezoelectric quartz resonators,and free acetone and phenol concentrations are determined; if kinetic coefficient γ=0.2±0.05 for 2 piezoelectric quartz resonators with polyethylene glycol sebacate (PEGSb) and trioctyl phosphine oxide (TOPhO) modifiers, then equilibrium gas phase over phenol formaldehyde resin contains phenol, and if A(PEGSb/TOPhO)=2.2±0.2, then equilibrium gas phase over phenol formaldehyde resin contains acetone.EFFECT: using this method enables determination of acetone and phenol without preliminary concentration and any other multistage sample preparation.1 cl, 1 ex |
