Shampoo and Conditioner Science 106 for such 18-MEA deficient hair would be in its drying behavior rather than its wetting characteristics. The low receding contact angle would tend to “pin” the water to the hair. This would lead to longer drying times during which the capillary forces imparted by the water between hair fibers would tend to cause the hair fibers to clump and entangle. The inclusion of 18-MEA in prototype conditioner formulations that were based upon stearoxypropylmethylamine, dimethylaminopropylstearamide and stearyltrimethylammonium chloride left the conditioner on the hair surface and this in turn yielded improvements in inter-fiber lubricity due to improved deposition at the hair surface. Conditioning Polymers in Hair Straightening Applications The two main processes for relaxing or straightening hair are hair treatment with a reducing agent to cleave the disulphide cystine bridges (S--S) within the hair structure, and treatment of stretched hair with a strong alkaline agent. Repeated relaxation treatments can cause significant hair damage, to both the cuticles and the cortex. The damage can be assessed by measuring the porosity of the hair, and the porosity of the keratin fibers can be measured by fixing 2-nitro-para-phenylenediamine at 0.25% in an ethanol/buffer mixture (10:90 volume ratio) at pH 10 at 37°C for 2 minutes. Cationic and amphoteric polymers such as polyquaternium-6, polyquaternium-7 and polyquaternium-39, added to hair relaxer formulations, mitigate this degradation of the hair structure. Also, the inclusion of high molecular-weight (106 g/mole) copolymers of acrylamide and diallyldimethylammonium chloride, acryloyloxytrimethylammoniumchloride, or acryloyloxyethyldimethylbenzylammonium chloride in the relaxing formula results in significant reduction in the hair structural damage caused by alkaline relaxation. Conditioning Polymers Cationic conditioning polymers are used to enhance the