十二烷基二甲基氧化胺
十二烷基二甲基氧化胺性狀：
外觀：無(wú)色透明粘稠狀液體；
電離性：弱陽(yáng)離子；
配伍性：本品能與陽(yáng)離子、非離子表面活性劑配伍；
穩(wěn)定性：不宜在100°C以上長(zhǎng)時(shí)間加熱；
質(zhì)量指標(biāo)：
外觀：無(wú)色透明粘稠狀液體；
活性物含量：30±2%；
PH值：6.0-8.0
性能與用途：無(wú)色透明粘稠狀液體，易溶于水，在水溶液中顯示非離子或陽(yáng)離子特性。當(dāng)pH值＜7時(shí)呈陽(yáng)離子性。氧化胺本身是優(yōu)良的洗滌劑，能產(chǎn)生穩(wěn)定而豐富的泡沫。主要用于餐具洗滌劑和工業(yè)液體漂白劑，有增泡穩(wěn)泡作用，并能改善增稠劑的相容性和產(chǎn)品的整體穩(wěn)定性。亦用作香波、液體洗滌劑和泡沫浴的泡沫促進(jìn)劑、調(diào)理劑、增稠劑和抗靜電劑。
十二烷基二甲基氧化胺水溶性：由于氧化胺分子中存在極性鍵N→0，偶極距為4.38D，所以該化合物具有極性大、熔點(diǎn)高的特性，易溶于水和低碳醇等極性溶劑中，而難溶于礦物油、苯等非極性溶劑。
在水溶液中氧化胺大量地以水合物(R1R2R3NO·XH2O)形式存在，但隨pH值的變化，會(huì)發(fā)生極性的轉(zhuǎn)變，如在pH>7的堿性溶液中，主要呈陰離子表面活性劑性質(zhì)。但在pH<3時(shí)的酸性溶液中，氧化胺主要以陽(yáng)離子的形式存在。氧化胺水溶液具有微弱的氧化性，在化妝品中正是利用其微弱的氧化性使皮膚達(dá)到白晰的目的。
十二烷基二甲基氧化胺表面活性：
（1）表面張力：加入氧化胺后，水的表面張力會(huì)大大降低，如純水的表面張力為72.80×10-3N/m。在各種氧化胺的臨界膠束濃度(cmc)時(shí)的表面張力均在30×10-3N/m左右。在cmc時(shí)氧化胺的表面張力比季銨鹽低得多，所以氧化胺的表面活性比季銨鹽好。
（2）去污性：氧化胺與AES或AS混合時(shí)，對(duì)去污有協(xié)同作用，但與LAS混合時(shí)，其協(xié)同作用不大。洗滌唇膏的產(chǎn)品采用12％脂肪酸(C12:C18=12:1)，13％非離子表面活性劑，12％LAS，如加入一定量的氧化胺，清洗作用會(huì)很好。
（3）乳化力：乳化力是衡量乳化劑好壞的一個(gè)指標(biāo)。如將氧化胺水溶液和石油溶劑在70℃下以同等條件乳化，然后靜止觀察乳化后體積的變化情況。結(jié)果表明，在氧化胺同系物中，乳化能力隨長(zhǎng)鏈烷基碳數(shù)的增加而增加。氧化胺作為乳化劑的另一個(gè)特點(diǎn)是可以在很寬的pH值范圍內(nèi)發(fā)揮乳化作用，特別是在酸性介質(zhì)中它可以與作為防腐劑、殺菌劑的季銨鹽陽(yáng)離子配伍，不但不會(huì)阻滯防腐劑的防腐性能，而且可增強(qiáng)其防腐性能，這是其他非離子表面活性劑所不能及的。
（4）起泡和穩(wěn)泡力：氧化胺是一種高效的穩(wěn)泡劑，常用于洗衣液或餐具洗滌劑中，用量l％～5％的產(chǎn)品性能溫和，對(duì)眼睛亦無(wú)刺激，抗硬水性好，在pH=9，300mg/kg的硬水中泡沫反而更高。脂肪醇硫酸鈉(AS)與氧化胺混合時(shí)，泡沫豐滿而穩(wěn)定，即使有油脂存在亦無(wú)變化，故常與陰離子型活性劑如LAS、AS、AES、SAS等配合使用，防刺激效果很好。氧化胺所產(chǎn)生的泡沫具有乳脂感，廣泛用于香波和淋浴制品中。
（5）增稠作用：氧化胺有較好的增稠作用，例如氧化胺與AES混合(1:9)的質(zhì)量分?jǐn)?shù)為15％活性物溶液(以下％均為質(zhì)量分?jǐn)?shù))，在酸性介質(zhì)中，即使鹽分很少，增稠效果亦明顯，且溫和，調(diào)理性好。氧化胺4.5％，AES 8.5％，NaCl 4％，pH=8，黏度(20℃)達(dá)7Pa·s，渾濁點(diǎn)<-5℃，但對(duì)香波的增溶增稠，碳原子以C14為佳。氧化胺的增稠作用亦可應(yīng)用于高堿性的漂白液中(9％C12，0.5％NaOH，4％Na2CO3，少量氧化胺)，10％HCl溶液加入了1.5％二羥乙基牛油基氧化胺及1.5％的牛油基二甲基氯化銨可使稠度增至1Pa·S。
http://www.youkaitea.com/threestyle/mh1631/firstcatalog/2798089/1.html
Dodecyl dimethylamine oxide
Product characteristics
Appearance: Colorless transparent viscous liquid;
Ionization: weak cation;
Compatibility: This product can be compatible with cationic and non-ionic surfactants;
Stability: It is not advisable to heat for a long time above 100 ° C
Quality indicators:
Appearance: Colorless transparent viscous liquid;
Active substance content: 30 ± 2%;
PH value: 6.0-8.0
Performance and application: Colorless and transparent viscous liquid, easily soluble in water, exhibiting non-ionic or cationic properties in aqueous solutions. When the pH value is less than 7, it becomes cationic. Amine oxide itself is an excellent detergent, which can produce stable and rich foam. Mainly used as tableware detergent and industrial liquid bleach, it has foaming and stabilizing effects, and can improve the compatibility of thickeners and the overall stability of products. It is also used as foam promoter, conditioner, thickener and antistatic agent for shampoo, liquid detergent and foam bath.
Water solubility of dodecyldimethylamine oxide: Due to the polar bond N → 0 and dipole distance of 4.38D in the amine oxide molecule, this compound has the characteristics of high polarity and high melting point. It is easily soluble in polar solvents such as water and low-carbon alcohols, but difficult to dissolve in non-polar solvents such as mineral oil and benzene.
In aqueous solutions, a large amount of amine oxide exists in the form of hydrates (R1R2R3NO · XH2O), but polarity changes with pH values. For example, in alkaline solutions with pH>7, it mainly exhibits anionic surfactant properties. But in acidic solutions with pH<3, amine oxide mainly exists in the form of cations. Amine oxide aqueous solution has weak oxidizing properties, which are utilized in cosmetics to achieve skin whitening.
Surface activity of dodecyl dimethylamine oxide:
(1) Surface tension: After adding amine oxide, the surface tension of water will be greatly reduced, for example, the surface tension of pure water is 72.80 × 10-3N/m. The surface tension at the critical micelle concentration (cmc) of various amine oxides is around 30 × 10-3N/m. At cmc, the surface tension of amine oxide is much lower than that of quaternary ammonium salts, so the surface activity of amine oxide is better than that of quaternary ammonium salts.
(2) Cleanliness: When amine oxide is mixed with AES or AS, it has a synergistic effect on cleaning, but when mixed with LAS, its synergistic effect is not significant. The product used to wash lipstick is 12% fatty acid (C12: C18=12:1), 13% non-ionic surfactant, 12% LAS. If a certain amount of amine oxide is added, the cleaning effect will be very good.
(3) Emulsifying power: Emulsifying power is an indicator of the quality of emulsifiers. If the aqueous solution of amine oxide and petroleum solvent are emulsified under the same conditions at 70 ℃, and then the volume change after emulsification is observed by standing still. The results indicate that the emulsifying ability increases with the increase of long-chain alkyl carbon number in amine oxide homologs. Another characteristic of amine oxide as an emulsifier is its ability to emulsify over a wide pH range, especially in acidic media. It can be combined with quaternary ammonium cations as preservatives and fungicides, which not only does not hinder the anti-corrosion performance of preservatives, but also enhances their anti-corrosion performance, which is different from other non-ionic surfactants
