Nonwoven Mat Binder Composition for Reduced Permeability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Nonwoven glass mats used as facers for gypsum and polyiso boards are permeable, leading to material bleed-through, which requires additional coating layers and increased costs due to additional raw materials and processing equipment.
Innovation Solution
A nonwoven mat comprising reinforcing fibers and a binder composition containing a polycarboxy polymer and polymer microspheres with a thermoplastic shell encapsulating a blowing agent and magnesium hydroxide, which reduces permeability and increases caliper through expansion upon heating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a coating layer is applied to the nonwoven glass mat to reduce permeability, then the bleed-through problem is solved, but the production cost increases due to additional raw materials and processing equipment
Solution Approach 1:
The invention merges the binder composition and coating layer into a single integrated composition applied directly to the glass fibers during mat formation. The binder composition contains polymers that simultaneously bind fibers together and form a permeability-reducing coating layer, eliminating the need for separate coating equipment and processes while achieving both fiber binding and bleed-through prevention
Solution Approach 2:
The binder composition serves multiple functions: it binds glass fibers together to form the mat structure, reduces permeability to prevent bleed-through, and provides surface coating properties. This multi-functional composition eliminates the need for separate specialized equipment for each function, reducing overall device complexity
2Reliability
If a coating layer is applied to the nonwoven glass mat to reduce permeability, then the bleed-through problem is solved, but the basis weight increases which increases transportation costs
Solution Approach 1:
The binder composition and coating layer are merged into a single composition applied during mat formation. This integration ensures that the coating material is used efficiently to bind fibers and reduce permeability simultaneously, minimizing the total quantity of substance needed compared to applying a separate coating layer that would add to the basis weight
3Reliability
If additional binder composition is used to reduce permeability, then the bleed-through problem is solved, but the loss on ignition increases which increases production cost
Solution Approach 1:
The invention changes the chemical composition parameters of the binder to include polymers with appropriate molecular weight, functional groups, and composition ratios that provide effective permeability reduction and fiber binding at lower concentrations. This optimization reduces the total amount of binder needed, thereby reducing loss on ignition and production costs while maintaining bleed-through prevention
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 mat achieves reduced permeability and increased caliper without significantly increasing loss on ignition or basis weight, effectively preventing material bleed-through.
Implementation Method 1
heating the wet laid mat to cure the binder composition and cause the polymer microspheres to expand
Implementation Method 2
Each of the polymer microspheres have a thermoplastic shell that encapsulates a blowing agent
Data Source
AI summary
A nonwoven mat and a method of making a nonwoven mat are provided. The nonwoven mat includes reinforcing fibers and a binder composition that includes a polycarboxy polymer and polymer microspheres. The binder composition may also include low-density fibers, such as microfibrillated cellulose fibers. The polymer microspheres have a thermoplastic shell that encapsulates a blowing agent. The thermoplastic shell has magnesium hydroxide on its outer surface. The components of the binder composition interact with one another and/or the reinforcing fibers to form a nonwoven mat having a less permeable structure and a higher caliper.