Computer Controlled Rotational Moulding of liquid polymers for the manufacturing of elastomeric prosthetic interface liners.

用于制造弹性假体界面衬垫的液体聚合物的计算机控制旋转成型。

• 批准号: 2473785
• 金额: --
• 依托单位: University of Strathclyde
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2473785
• 关键词: Computer; Controlled; Rotational; Moulding; liquid

Interface Liners play an important role in the comfort and health for prosthetic leg users. They fit over the residual limb and go between the limb and the socket (the socket is the shell that encases the limb and connects the user to the prosthesis. The liner is a protective cover made of a flexible, cushioning material. (typically silicone, polyurethane or co-polymer) Worn over the residual limb, it reduces movement and chafing between the skin and the socket. Liners are designed with specific characteristics to work with different suspension systems. Current manufacturing methods utilise a cavity moulding technique where liquid not polymerised resin is gravity fed or pressure injected in a fixed volume cavity. The established liner manufacturers offer a considerable liner range with different sizes to accommodate for the diversity within the western amputee population. After curing of the liquid material, the moulds are separated and the product removed from the cavity. This process has a high quality consistency but the manufacturing of moulds is complex and expensive and therefore driving up the product costs. In addition, multiple cavities are needed when more than one material behaviour is required such as hard and soft areas. An exciting and innovative manufacturing technique is the liquid rotational moulding process aiming at using standard injection-moulding polymer grades normally used in the manufacturing of interface liners. In this process, the 2 component polymer is injected into a single mould rotating around two axes. Rotational moulding in two axes has the advantage of producing hollow products. Previously, the inherent difficulty was in the production of objects with uniform thickness since the speed of the two primary axes are fixed and cannot be varied independently to take into account the changes in material properties such as its density and viscosity. With the advent of computers, it is now possible to control the thickness of the object accurately. This is made possible by creating an intelligent software which takes in the viscosity and density time variation of the polymer and using the flat plate withdrawal theory, computes the new speed for each axis. The relationship between rotational moulding parameters and polymeric material properties for a room temperature vulcanisation (RTV) silicone rubber system to produce liners is the focus of this project. In addition, the single rotational mould approach will deliver, beside, off the shelf products a truly personalised capability for the manufacturing of bespoke multi material/behavioural liners.

界面衬垫在假肢使用者的舒适性和健康方面发挥着重要作用。它们安装在残肢上，位于肢体和插座之间(插座是包裹肢体并将使用者连接到假肢的外壳)。衬垫是由柔性缓冲材料制成的保护罩。(通常是硅胶、聚亚安酯或共聚聚合物)戴在残肢上，可以减少皮肤和眼窝之间的运动和摩擦。衬垫的设计具有特定的特性，以与不同的悬挂系统一起工作。目前的制造方法使用型腔成型技术，其中未聚合树脂的液体被重力输送或在固定体积的型腔中压力注射。成熟的班轮制造商提供了相当多的不同尺寸的班轮，以适应西方截肢者群体的多样性。液体材料固化后，将模具分离，并将产品从型腔中取出。这一工艺具有高质量一致性，但模具制造复杂且成本高昂，因此推高了产品成本。此外，当需要一种以上的材料性能时，如硬质和软质区域，需要多个型腔。一种令人兴奋和创新的制造技术是液体旋转模塑工艺，旨在使用标准的注塑聚合物牌号，通常用于制造界面衬里。在这一过程中，将双组分聚合物注射到绕两个轴旋转的单个模具中。双轴回转成型具有生产中空制品的优点。以前，由于两个主轴的速度是固定的，并且不能独立地改变以考虑其密度和粘度等材料属性的变化，因此固有的困难在于生产具有均匀厚度的物体。随着计算机的出现，现在可以精确地控制物体的厚度。这是通过创建一个智能软件来实现的，该软件考虑了聚合物的粘度和密度随时间的变化，并使用平板退出理论来计算每个轴的新速度。旋转成型参数与室温硫化(RTV)硅橡胶体系生产衬里的聚合物材料性能之间的关系是本项目的重点。此外，除了现成的产品外，单一旋转模具方法还将提供真正个性化的能力，用于制造定制的多种材料/行为内衬。