Spray Drying Thermoplastic Powder for Spherical Geometry
Solution Overview
Problem
Existing thermoplastic molding compound powders have low bulk density and poor flowability due to jagged geometry and varying particle sizes, which hinder applications requiring high packing density and even layer application in technologies like powder foaming and additive manufacturing.
Innovation Solution
The method involves producing spherical thermoplastic molding compound particles through spray drying a suspension of ceramic, metallic, or vitreous substrate particles in a solvent with a dissolved polymer binder and plasticizer, promoting high bulk density and flowability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If grinding process is used to produce powdered feedstock mass, then particle size can be controlled, but particle geometry becomes jagged resulting in low bulk density and poor flowability
Solution Approach 1:
The invention replaces the conventional grinding process with a spray drying process that produces spherical particles. The suspension is atomized into droplets that evaporate to form spherical molded compound particles, eliminating the jagged geometry inherent in ground powders and thereby improving bulk density and flowability
2Ease of operation
If grinding process is used to produce powdered feedstock mass, then particle size can be controlled, but flowability deteriorates due to fragmented geometry
Solution Approach 1:
The spray drying process generates spherical particles that flow more freely compared to jagged ground particles. The spherical geometry reduces interparticle friction and improves flowability, enabling better handling and processing in subsequent manufacturing steps
3Manufacturing precision
If conventional powdered molding compounds are used, then manufacturing process is simple, but packing density and layer uniformity are poor
Solution Approach 1:
The invention introduces a spray drying process to produce spherical particles with uniform size distribution. This additional processing step enables superior layer uniformity and packing density in subsequent manufacturing operations, justifying the increased process complexity through significant quality improvement
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The resulting spherical particles achieve high bulk density and improved flowability, enhancing the packing and layering processes in applications such as selective laser sintering and 3D printing, leading to increased sintering density and efficient processing.
Implementation Method 1
During spray drying of the suspension, the solvent completely passes into the gas phase
Data Source
Figure 1~3
AI summary
The present invention relates to a process for producing thermoplastic molding compound powder, which consists of or comprises spherical or approximately spherical molding compound particles, from a suspension of glassy and/or ceramic and/or metallic substrate particles in a solvent in which a binder is dissolved, the binder comprising a polymer soluble in the solvent, wherein the binder further comprises one or more additives soluble in the solvent, the process comprising the step of spray drying the suspension, wherein the spray drying is carried out in such a way that the solvent partially or completely passes into the gas phase.