Membrane Technologies

Application of PVDF hollow fiber via SCINOR’S TIPS

Beijing Scinor Membrane Technology Co., Ltd. (Scinor-Beijing), located in Beijing, China, is devoted to the research, development, sales and manufacture of membrane materials, modules and modularised equipment. The company is the first to establish the commercial process of the TIPS Ultrafiltration fibre and modules with polyvinylidene fluoride (PVDF) materials based on four patented technologies from Tsinghua University.

Scinor-Beijing’s product positioning strategy is defined by its high-end TIPS UF membrane. These high-flux materials are chemical-resistant, consume low levels of energy and easy to maintain. Scinor-Beijing’s membrane products have provided a number of solutions to more than 130 industrial and municipal clients in the water and wastewater industries locally and abroad. These include water purification for potable and non-potable purposes, wastewater treatment, water reuse, and seawater desalination.

Scinor exports products to America, Japan, South Korea and Australia, among others, and has established offices in America and Singapore.

With continuous technological input, premium products and a strong team consisting of the most experienced professionals, Scinor has built a strong brand in China as Scinor-Beijing and vows to grow into an internationally-recognised membrane manufacturer in the foreseeable future. 

TIPS and NIPS – not every PVDF is created equal
In recent years, most ultrafiltration membrane manufacturers have chosen PVDF to create hollow fibre (HF) membranes for the growing water market. The requirements for high flux rates, appropriate pore size, reliable membrane integrity, mechanical strength and durability, cleaning chemical compatibility, and low costs, have made PVDF the preferred polymer over other available materials on the market such as PAN, PES, and PE, and alternative materials such as ceramic membranes.

There are two basic methods for creating PVDF HF membranes: the Non-Solvent Induced Phase Separation (NIPS) and the Thermally Induced Phase Separation (TIPS) methods. 

NIPS membranes are anisotropic (i.e., mechanical properties vary depending on the direction in which they are measured). They exhibit a “skinned” structure, with tight inner and outer surface pores, typically with a rating of 0.02µm – 0.04µm, supported by a finger-like structure that does not provide any filtration capability. 

TIPS membranes are isotropic, with mechanical properties that are the same in all directions.  The pore structure of Scinor TIPS is slightly larger at 0.1µm, but this has almost no measurable effect on performance.  The structure is continuous throughout the membrane, providing mechanical strength and a more reliable filtration integrity.

The Scinor TIPS process is a patented manufacturing process for PVDF hollow fibre membranes developed by scientists at the prestigious Tsinghua University in Beijing. Compared to the NIPS membranes, Scinor’s TIPS membranes exhibit higher flux, mechanical strength (meaning low fiber breakage), and chemical tolerance.  The homogeneous sponge-like structure is permanently hydrophilic and extremely consistent as a result of Scinor’s precision automated production line.  Scinor has passed the NSF61, NSF 419 Test as well as ISO90001, and proven to be able to consistently provide high quality and safe products.

SEM of TIPS membrane. Note the ‘finger’ shape of the pore structure.


SEM of TIPS fiber. Note the isotropic structure.(SCINOR’S)