Enhancing Reverse Osmosis Membrane Performance Using Polyquaternium-10 (PQ10) in Surface Coating Technology
Lue, Zhenhua, et al. Desalination 564 (2023): 116755.
This case study highlights the use of Polyquaternium-10 (PQ10), a cationic cellulose derivative, in combination with polyvinyl alcohol (PVA), to enhance the functionality of polyamide-based RO membranes through an advanced surface coating strategy.
Formulation & Coating Approach
A surface coating layer comprising PVA blended with PQ10 was applied to polyamide (PA)-based RO membranes, followed by chemical cross-linking. The addition of PQ10 was aimed at modifying the coating's physical and chemical characteristics by reducing crystallinity of the PVA matrix, enhancing water permeability, neutralizing surface charge, promoting a near-neutral surface environment, and creating pseudo-zwitterionic surfaces, improving resistance to both positively and negatively charged foulants.
Key Results:
· Water Permeability: The incorporation of 0.2% PQ10 into a 1.0% PVA coating significantly reduced hydraulic resistance from 5.9 × 1012 m-1 to 2.5 × 1012 m-1, indicating enhanced water transport.
· Anti-Fouling Capability: Maintained PVA's resistance to negatively charged foulants. Improved performance against positively charged foulants, attributed to PQ10's modulation of surface charge and pseudo-zwitterionic properties.
· Extended Dye Wastewater Filtration Performance: PVA/PQ10-coated membrane that had a slightly lower initial water permeability than the bare membrane had higher salt rejection, lower flux decline, and a higher cumulative amount of permeate after 48 h filtration.
· Chemical Resistance: Soaking test results demonstrated enhanced resistance to acid, alkaline, and chlorine, which would prolong the lifetime of the membrane.
Optimizing Permanent Wave-Reducing Agents with Polyquaternium-10 for Damaged Hair
Chang, Mi-hwa, et al. The Korean Fashion and Textile Research Journal 24.6 (2022): 775-781.
This case study reports on the use of Polyquaternium-10 (PQ10) as a functional additive in a permanent wave-reducing agent with nicotinoyl dipeptide-23.
Formulation Approach: A range of formulations were developed, which consisted of 0.1%-1.0% polyquaternium-10 added to a cysteine permanent reagent containing nicotinoyl dipeptide-23. The PQ10 was used as a conditioning polymer to assist in moisture retention and protecting the hair fiber during chemical waving
Key Results:
· pH Stability: The formulations were pH-stable over time, with the 0.1%-0.6% PQ10-containing formulations exhibiting the highest compatibility based on hair's natural pH balance.
· Thermal Stability: At room temperature and at increased temperature, all of the formulations were stable. When tested at 0 °C, the 0.9% and 1.0% PQ10-containing formulations coagulated, demonstrating a limited compatibility at high levels of PQ10 at lower temperatures.
· Wave Efficiency vs. PQ10 Content: Formulations with increasing PQ10 content showed slightly decreased efficiency in forming waves, with higher PQ10 content resulting in weaker but longer-lasting curls. Lower concentrations of PQ10 were more effective for short-term wave-setting strength.
· Moisture Retention: A positive correlation was observed between PQ10 concentration and hair moisture content after treatment, suggesting that PQ10 enhances hydration of the hair fiber.
· Formulation Texture: As PQ10 concentration increased, the formulation's consistency shifted from liquid to viscous, which may benefit application control and adherence to hair strands during treatment.