Performance properties of Alkyl Polyglycosides in Personal Care Products

• Concentrates

Addition of alkyl polyglycosides modifies the rheology of concentrated surfactant mixtures so that pumpable, preservative-free and readily dilutable concentrates containing up to 60 % active substance can be prepared.

A concentrated mixture of these ingredients is usually used as a cosmetic ingredient or, in particular, as a core concentrate in the production of cosmetic formulations (e.g. shampoo, shampoo concentrate, foam bath, body wash, etc.).

Thus, alkyl glucosides are based on highly active anions such as alkyl ether sulphates (sodium or ammonium), Betaines and/or non-ionic surfactants and are therefore more mild to the eye and skin than traditional systems. At the same time, they show excellent foaming performance, thickening performance and processing performance. Super concentrations are preferred for economic reasons because they are easier to handle and dilute and do not contain hydrogen. The mixing ratio of the surfactant base is adapted to the performance requirements of the formulations.

•  Cleansing effect

The cleaning performance of surfactants can be compared through fairly simple tests. The pig epidermis treated with the mixture of sebum and smoke surfactant was washed with a 3% surfactant solution for two minutes. In the microscopic range, the gray value is determined by digital image analysis and compared with untreated pig skin. This method produces the following levels of cleaning properties: lauryl glucoside produces the best results, while coconut amphoteric acetate produces the worst results. Betaine, sulfosuccinate and standard alkyl ether sulfate are in the middle range and cannot be clearly distinguished from each other. At this low concentration, only lauryl glucoside has a deep pore cleansing effect.

•  Effects on hair

The mildness of alkyl glycosides on the skin is also reflected in the care of damaged hair.Compared with the standard etheric acid solution, alkyl glucoside solution to perm tensile strength of the reduction is much smaller.Alkyl polyglycosides can also be used as surfactants in dyeing, wave proofing and bleaching agents due to their excellent water retention and alkali stability.Studies on the constant wave formula show that the addition of alkyl glucoside has a good effect on the alkali solubility and wave effect of hair.

The adsorption of alkyl glycosides on hair can be proved directly and qualitatively by X-ray photoelectron spectroscopy (XPS).Split the hair in half and soak the hair in a solution of 12% sodium lauryl polyether sulfate and lauryl glucoside surfactant at pH 5.5, then rinse and dry.Both surfactants can be tested on hair surfaces using XPS.Ketone and ether oxygen signals are more active than untreated hair.Because this method is sensitive to even small amounts of adsorbents, a single shampoo and rinse is not enough to distinguish between the two surfactants.However, if the process is repeated four times, the XPS signal does not change in the case of sodium laureth sulfate compared to untreated hair.In contrast, the oxygen content and ketone functional signal of lauryl glucoside increased slightly.The results showed that alkyl glucoside was more substantial to hair than standard ether sulfate.

The affinity of surfactant to hair affects the comb ability of hair.The results showed that alkyl glucoside had no significant effect on wet combing.However, in mixtures of alkyl glycosides and cationic polymers, the synergistic reduction of wet binding properties was approximately 50%.In contrast, alkyl glucosides significantly improved dryness.Interactions between individual hair fibers increase the volume and manageability of the hair.

The increased interaction and film-forming properties also contribute to the styling effect.The omni-directional bounce makes the hair appear vibrant and dynamic.The rebound behavior of hair curls can be determined by an automated test (Figure 8) that studies the torsion characteristics of hair fibers (bending modulus) and hair curls (tensile force, attenuation, frequency and amplitude of oscillations).The free attenuation oscillation force function was recorded by measuring instrument (inductive force sensor) and processed by computer.Modeling products increase the interaction between the hair fibers, increase the curl          vibration tensile strength, amplitude, frequency and attenuation value.

In the lotions and regulators of fatty alcohols and quaternary ammonium compounds, the synergistic effect of alkyl glucoside/quaternary ammonium compounds was beneficial to reduce the wet binding property, while the dry binding property was only slightly reduced.Oil ingredients can also be added to the formula to further reduce the necessary formaldehyde content and improve hair shine.This oil-water emulsion can be used to “rinse” or “hold” hair for post-treatment preparation.