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Formulating Conditioning Products for Hair and Skin
Published in Randy Schueller, Perry Romanowski, Conditioning Agents for Hair and Skin, 2020
Dimethicone (polydimethyisiloxane) provides substantial conditioning effects to both hair and skin when properly delivered in appropriate quantities. Incorrectly formulated, dimethicone also has the potential to leave hair or skin feely tacky, greasy, and prone to attracting environmental dust and debris. The formulating challenge of delivering just the appropriate quantity of this category of materials is particularly acute for hair care products, since they are typically rinsed after application. If the dimethicone droplets are not sufficiently small, or adequately suspended, they will coalesce and settle out of the system. If they are emulsified by surfactants, they will, predominantly, be carried away with the rinse water and be of little or no value to the hair. Procter and Gamble researchers found a solution to this problem by suspending discrete dimethicone droplets with the aid of a natural gum.
Products used on the vulva
Published in Miranda A. Farage, Howard I. Maibach, The Vulva, 2017
Miranda A. Farage, Lisa Lennon
Several alternative forms of reusable menstrual protection products are available from specialty shops or the internet. Some women see these as a more environmentally friendly alternative to disposable products. Examples are shown in Figure 37.4. Menstrual cups are flexible, nonabsorbent containers made of natural gum rubber or medical silicon inserted into the vagina that can collect about 1 oz of menstrual fluid. They can then be emptied, washed, and reused. Sea sponges are also sold for menstrual protection, as are interlabial pads sewn from fabric or made from absorbent yarn (i.e., knitted or crocheted). Disposable interlabial pads are composed of materials similar to modern tampons. These are worn externally and held in place by the labia. They are most suited for light menstrual flow. For any reusable device, care must be taken to thoroughly clean and sanitize the product between uses.
Synthetic Polymers in Cosmetics
Published in E. Desmond Goddard, James V. Gruber, Principles of Polymer Science and Technology in Cosmetics and Personal Care, 1999
E. Desmond Goddard, James V. Gruber
It is well recognized in polymer science that covalently cross-linking polymers (that is, hooking two polymer chains together by periodic insertion of a difunctional monomer that can react with both chains) radically alters their properties. Perhaps the most wellknown instance of functional cross-linking occurs in the vulcanization of rubber. Rubber is a natural gum, which, when harvested from the rubber tree, is a tacky, flowing resin. It was found that by heating the gummy resin with elemental sulfur, a process known as vulcanization, the liquid rubber could be converted via covalent cross-linking into the firm rubber characteristic of automobile tires.
De-esterified tragacanth-chitosan nano-hydrogel for methotrexate delivery; optimization of the formulation by Taguchi design
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Komail Sadrjavadi, Behzad Shahbazi, Ali Fattahi
Gum tragacanth is an acidic heteropolysaccharide, which is comprised of an acidic water-swellable major component, bassorin, and a water-soluble component, tragacanthin. Tragacanth, as a natural gum, has the mentioned advantages for biopolymers but has the limitations of low water solubility and the possibility of forming only weak water-insoluble gels. In order to overcome these typical limitations of tragacanth, de-esterified tragacanth (DET) has been prepared by Fattahi et al. [2]. DET is a water-soluble analog of tragacanth gum that contains a highly branched, high molecular weight de-acetylated tragacanthic acid. It possesses the ability to form stable gels by the ionotropic complex with positive charge polymers like chitosan and cationic metal ions such as zinc and iron [2,6]. Regarding the properties of DET, it could be a proper polymer to produce hydrogels with complex coacervation process together with a positively charged polymer e.g. chitosan.