NEUTRALIZATION OF CARBOXYLIC RESIN 129 200 AMP AMPD ._• 150 AS • AEPD •100 •0 o , •'o ' do ' ½o ' % Relative Humidity Figure 3, Hygroscopicity of variou amino alcohols rs. relative huidity at 30øC 4O ½ 3o •o DEA T I PA TEA MEA AMP AB AMPD A[PD •o , 7t ' do ' ½o ' % Relative Humidity Figure 4. Hygroscopicity of VEM resin 90% neutralized with various amino alcohols vs. relative humidity at 30 ø C Table II Hygroscopicity of Amino Alcohols at 85% RH and 30øC Weight Gain Mol Wt g/100 g g/real AMP 89.14 125 AB 89.14 110 98 AEPD 119.16 72 86 AMPD 105.14 103 108 MEA 61.09 205 125 DEA 105.14 103 108 TEA 149.19 70 104 MIPA 75.11 170 128 DIPA 133.19 90 120 TIPA 191.27 37 71 Additionally, the variation in solubility of neutralized resin in an- hydrous ethanol (50% and 3% total solids) and ethanol-Freon mixtures

130 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table III Sward Hardness of Films a at 75 øF 17% RH 24% RH AMP 66 64 AB 72 70 AEPD 66 66 AMPD 66 64 MEA 64 64 DEA 66 66 TEA 68 68 TIPA 64 66 3.8 X 10 -a cm dry films of VEM resin 90% neutralized with various amino alcohols. Table IV Clarity of Solutions of VEM Resin 90% Neutralized with Various Amino Alcohols at Room Temperature • 50% Total Solids 3% Total Solids 35%' 5% Total Solids in EtOH in EtOH 65%:12/11-35/65 AMP 0 0 0 AB 0 0 0 AEPD 0 0 0 AMPD 0 0 0 MEA 3 2 DEA 3 2 TEA 0 0 0 TIPA 0 0 0 • 0, clear solution 1, slightly cloudy solution with small separation 2, slightly cloudy solu- tion with no separation in 2 weeks 3, cloudy solution with no separation in 2 weeks. was determined at room temperature. Table IV shows that only ethanol- amine and diethanolamine decrease the solubility of 90% neutralized VEM resin in these systems. But when the VEM resin is neutralized to 65%, all solutions are clear. SUMMARY Although AMPD is the most widely used base for the neutralization of carboxylic-type hair spray resins, other amino alcohols can be used for this purpose as well. It was found that the tested amino alcohols have only a negligible effect on the hygroscopicity and Sward Hardness of the resin neutralized with these amino alcohols. Most of the amino alcohols do not decrease the solubility of the 90% neutralized VEM resin. If de-