Preparation Method of Medical Composite Film

A medical composite film material comprising polyurethane and acetate‑based starch; in the present invention, the use of acetate‑based starch enables an improvement in… Medical composite film On the one hand, it exhibits good breathability; on the other hand, acetate‑based starch particles absorb water molecules from within and, under external pressure, rapidly diffuse into the composite membrane. ; Moreover, the incorporation of acetylated starch granules enables the alkaline aqueous solution to adsorb onto their surfaces, disrupting the dense internal structure of the polyurethane matrix, thereby creating additional pathways for water molecules and increasing Medical composite film its breathability and moisture permeability; now, let’s take a look together. Medical composite film The preparation method, then. 。

The present invention relates to the field of medical materials and is capable of preventing subcutaneous tissue edema. When skin injury occurs, timely dressing application is required to protect the wound and alleviate pain.

Currently, commonly used dressings in clinical practice include cotton cloth and gauze; however, these materials lack moisturizing properties, tend to form crusts, and their permeability can increase the risk of exogenous infections. The material is soft and exhibits strong absorbency, providing some protection to the wound surface; however, it fails to meet the demands of clinical medical practice and is prone to eliciting rejection reactions in the human body. Biologically derived materials such as porcine and ovine skin currently used in clinical settings suffer from shortcomings in strength, elasticity, moisture permeability, and moisture‑absorbing drainage, while their storage and transportation are cumbersome, thereby limiting their large‑scale application.

Medical composite film It has been applied in the medical field; when adhered to the skin surface, it can easily cause the skin to appear pale. Polyurethane. Medical composite film Although it offers some waterproof and moisture-permeable properties, its breathability and moisture vapor transmission are poor, causing patient discomfort.

Medical composite film In view of the drawbacks of the prior art, a material with excellent air and moisture permeability is provided. Medical composite film Materials, while also providing those containing polyurethane and acetate starch. Medical composite film Method for preparing the material.

Medical composite film The material preparation method comprises the following steps:

1. Polyurethane is dissolved in N,N-dimethylformamide to prepare a polyurethane solution with a solid content of 20–50%.

2、 Dissolve the acetylated starch component in a polyurethane solution to obtain a coating-forming liquid. ;

3. Pour a casting solution onto one side of the cellophane substrate, then use an applicator to evenly press it onto the opposite side, ensuring that the substrate is completely covered with a uniform, smooth layer of the casting solution.

4. Place the coated film-forming solution together with the substrate into an alkaline aqueous solution of pH 9–12; after film formation, remove the sample, wash it, and dry it, then peel it off from the substrate to obtain the sample membrane.

The present invention employs acetylated starch, which rapidly diffuses within the composite membrane under the influence of external atmospheric pressure. ; and the addition of acetylated starch granules enhances Medical composite film Permeability: on the other hand, acetate‑starch particles absorb internal water molecules, causing the alkaline aqueous solution to adsorb onto the surface of the acetate‑starch particles, thereby disrupting the dense internal structure of the polyurethane matrix, increasing water‑molecule pathways, and enhancing the gas and moisture permeability of the blend membrane.