Amphoteric Polymer Pitch Control Agent for High-pH Papermaking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pitch control agents, particularly amphoteric polymers, exhibit limited pitch controllability in high-pH environments such as the pulping process, leading to reduced dispersibility and fixability of micro-pitch, which restricts their applicability across different pH ranges in paper production.
Innovation Solution
An acrylamide-based amphoteric polymer with specific monomer composition, including a high content of (meth)acrylamide, diallyldialkylammonium salt, and α,β-unsaturated carboxylic acid monomers, is used as a pitch control agent, ensuring high dispersibility and fixability of micro-pitch across a wide pH range by neutralizing charges and forming a protective colloid.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional amphoteric polymers are used as pitch control agents, then pitch control is effective in neutral or acidic environments, but pitch controllability deteriorates in high-pH environments such as pulping process
Solution Approach 1:
The invention changes the chemical parameters of the polymer by incorporating specific monomer units with different charge characteristics. The copolymer contains cationic monomer units (quaternary ammonium groups) and anionic monomer units (carboxyl groups) in a specific ratio, allowing the polymer to maintain effectiveness across a wide pH range from acidic to high-alkaline conditions through charge balance adjustments
Solution Approach 2:
The invention creates a composite polymer structure by copolymerizing multiple types of monomers including (meth)acrylamide, cationic monomers with quaternary ammonium groups, and anionic monomers with carboxyl groups. This composite structure combines the benefits of different charge types, enabling the pitch control agent to function effectively in both pulping and papermaking processes across varying pH conditions
2Loss of substance
If porous inorganic material is used to adsorb micro-pitch, then micro-pitch can be removed from the system, but white water pollution and sludge deposition occur
Solution Approach 1:
The invention replaces the mechanical adsorption system (porous inorganic materials like talc or clay) with a chemical system based on polymer-micropitch complexation. The cationic and anionic monomer units in the copolymer chemically interact with micro-pitch through electrostatic forces and hydrogen bonding, forming soluble complexes that can be discharged with white water without causing pollution or sludge deposition
3Loss of substance
If porous inorganic material is used to remove micro-pitch, then micro-pitch is discharged from the system, but papermaking wires experience wear or damage
Solution Approach 1:
The invention replaces the mechanical action of porous inorganic particles (which cause wear through abrasion) with a chemical dissolution and complexation mechanism. The copolymer forms soluble complexes with micro-pitch that are discharged in the white water stream, eliminating the need for mechanical removal and thereby preventing wire wear and damage
4Object-generated harmful factors
If production lines are stopped to remove adhered pitch, then equipment contamination is eliminated, but productivity and workability are reduced
Solution Approach 1:
The invention applies preliminary action by adding the pitch control agent to the pulp slurry before the papermaking process begins. The copolymer prevents micro-pitch from agglomerating and adhering to equipment surfaces in the first place, eliminating the need for subsequent stopping and cleaning operations, thereby maintaining continuous production and high productivity
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 acrylamide-based amphoteric polymer maintains excellent pitch controllability in both pulping and papermaking processes, preventing agglomeration and ensuring effective discharge of micro-pitch, even under pH changes, thereby enhancing productivity and paper quality.
Implementation Method 1
an acrylamide-based amphoteric polymer having a specific monomer composition as a pitch control agent... the dispersibility of micro-pitch and the fixability of micro-pitch to pulp can be maintained
Implementation Method 2
forming a protective colloid... ensures high dispersibility and fixability of micro-pitch across a wide pH range
Data Source
AI summary
Disclosed is a pitch control agent including a (meth)acrylamide-based amphoteric polymer. The (meth)acrylamide-based amphoteric polymer contains 50 mol% or more of (meth)acrylamide, 0.5 to 20 mol% of a diallyldialkylammonium salt; and 0.1 to 14 mol% of an anionic monomer, as copolymerizable monomer components. This pitch control agent is less likely to be affected by a change in a surrounding environment, and therefore can exhibit excellent pitch controllability under various environments in paper production process.