Bipolar surfactants o surfactants o loʻo iai uma vaega anionic ma cationic hydrophilic vaega.

I le lautele o le tautala, amphoteric surfactants o mea faʻapipiʻi o loʻo i ai soʻo se lua vaega hydrophilic i totonu o le mole tutusa, e aofia ai le anionic, cationic, ma le nonionic hydrophilic vaega. Ole fa'aoga masani fa'aoga amphoteric o le tele o vaega hydrophilic ma ammonium po'o quaternary ammonium salts i le vaega cationic ma carboxylate, sulfonate, ma ituaiga phosphate i le vaega anionic. Mo se fa'ata'ita'iga, ole amino acid amphoteric surfactants ma amino ma vaega vaega i le mole e tasi o betaine amphoteric surfactants e faia mai i totonu masima o lo'o iai uma quaternary ammonium ma carboxyl vaega, ma le tele o ituaiga eseese.

O le fa'aaliga o fa'aola amphiphilic e eseese ma le tau o le pH o latou fofo.

Fa'aalia o mea totino o su'ega fa'asao i totonu o ala fa'asa'o; Fa'aalia o mea totino o so'o fa'agata anionic i fa'asalalauga alkaline; Fa'aali atu uiga o mea e le fa'aionika i fa'asalalauga fa'asalalau. O le mea e paleni lelei ai le cationic ma le anionic ua ta'ua o le isoelectric point.

I le tulaga isoelectric, ole amino acid type amphoteric surfactants i nisi taimi e fa'afefe, a'o betaine ituaiga surfactants e le faigofie ona pa'u e oo lava ile isoelectric point.

Ituaiga Betainesurfactants na muamua fa'avasegaina o quaternary ammonium salt compounds, ae le pei quaternary ammonium salts, e leai ni anion.
O le Betaine o lo'o fa'atumauina lona lelei mole mole mole ma mea fa'a-cationic i fa'asalalauga fa'asa'o ma alkaline. E le mafai ona maua e lenei ituaiga o su'ega ni tau lelei pe leaga. Faʻavae i luga o le tau o le pH o le vaifofo vai o lenei ituaiga o vailaʻau, e talafeagai le faʻavasegaina o se amphoteric surfactant sese.

E tusa ai ma lenei finauga, e tatau ona faʻavasegaina ituaiga faʻapipiʻi betaine e pei o cationic surfactants. E ui lava i nei finauga, o le tele o tagata faʻaoga betaine o loʻo faʻaauau pea ona faʻavasegaina i latou e pei o le amphoteric compound. I le tele o le heteroelectricity, o loʻo i ai se fausaga biphasic i luga ole gaioiga: R-N + (CH3) 2-CH2-COO -.

O le fa'ata'ita'iga sili ona taatele o sufactants ituaiga betaine ole alkylbetaine, ma o lona oloa sui o le N-dodecyl-N, N-dimethyl-N-carboxyl betaine [BS-12, Cl2H25-N + (CH3) 2-CH2COO -]. Betaine ma vaega amide [Cl2H25 i le fausaga ua suia e R-CONH - (CH2) 3-] e sili atu le faʻatinoga.

Ole malo ole vai e le afaina ai lebetainesurfactant. E maua ai foam lelei ma mautu lelei i vai vaivai ma vai malo. I le faaopoopo atu i le faʻapipiʻiina o mea faʻapipiʻi anionic i tulaga maualalo pH, e mafai foi ona faʻaaogaina faʻatasi ma le anionic ma cationic surfactants. E ala i le tu'ufa'atasia o le betaine ma le anionic surfactants, e mafai ona maua le viscosity lelei.