R31 are connected to silicon by a carbon-silicon bond.
The carbon numbers in the alkylene chain do not include the carbons in the extra segments or substitutions. Also, the polyamides must have a siloxane portion in the backbone and optionally may have a siloxane portion in a pendant or branched portion.
If repeated with no variations in the defined variables, Formula A is representative of a linear homopolymer. Variations of the invention include: (1) polyamides in which multiple values of DP, and of units X, Y, and R1-R4 occur in one polymeric molecule, and wherein the sequencing of these units may be alternating, random or block; (2) polyamides in which an organic triamine or higher amine such as tris(2-aminoethyl)amine replaces the organic diamine in part, to produce a branched or crosslinked molecule; and (3) physical blends of any of (1) and (2) and/or linear homopolymers.
These and other features of the invention will become apparent from a consideration of the detailed description.
Not applicable.

1. Field of the Invention
The present invention pertains generally to microfluidic flow devices and specifically to mixers and splitters of microfluidic flow.
2. Description of the Background
The application of microfluidic analytical devices to chemical or biological assays has developed rapidly over the last decade. Although microfluidic devices have been highly successful, several performance limitations exist, notably reagent mixing.
Most mixing devices rely on diffusive mixing, wherein the natural laminar flow effects and the reagent's inherent diffusion coefficient cause the reagents to mix. Therefore, the mixing chamber/channel is usually extended to lengths that will ensure a completely mixed outlet stream. This approach may be acceptable for low flowrates, but high flowrates (>1 cm/s) or low analyte diffusion coefficients (<10−7 cm/s2) will require excessively long mixing channels. The difficulty in rapidly mixing reagents results from the fact that the system is restricted to the laminar flow regime