Studies of the mechanical and thermal properties of cross‐linked poly(methylmethacrylate‐acrylic acid‐allylmethacrylate)‐modified bone cement

Abstract

Bone cement is used as load-distributing filler between the prosthesis and the bone, as well as a method to anchor prosthesis in orthopedic implants. One of the disadvantages of using polymethylmethacrylate (PMMA) as bone cement is shrinkage of the cement during polymerization. Shrinkage of the cement during polymerization may lose the good load transfer through the interface between the bone and bone cement, and is a source of prosthetic loosening. A crosslinked poly(methylmethacrylate-acrylic acid-allylmethacrylate) was applied to bone cement, because it was found that this copolymer exhibits the ability to absorb body fluids and swell in a controlled manner to compensate shrinkage of the cement during polymerization. In this study, the crosslinked poly(methylmethacrylate-acrylic acid-allylmethacrylate) modified bone cement was prepared and characterized using tensile analysis and dynamic mechanical analysis. The results show that the modified bone cement is able to enhance the mechanical properties of bone cement. From dynamic mechanical analysis, the transition temperature and the tan ␦ value of the cement may be affected by prepolymerized crosslinked poly(methylmethacrylate-acrylic acid-allylmethacrylate) powder. From the observation of the fracture surfaces of the cements, the modified bone cement may improve fracture toughness

DMA testing of epoxy resins: The importance of dimensions

“… Literature values of rubbery modulus data collected using SC . An assumed misplaced decimal point results in shifting the circled points the data to the left.…”

“…The DMA instrument manufacturers do suggest sample dimension ranges for given geometries , but do not discuss how a three order of magnitude modulus change through the glass transition can affect DMA measurements. Numerous researchers favor the 3pt bend geometry , other favor the DC geometry , and others favor the SC geometry . However, Duncan and others claim that the 3pt bend geometry is best suited for high modulus materials, such as metals, ceramics, and highly filled thermosetting polymers that show little change in modulus throughout the test .…”

Alternative acrylic bone cement formulations for cemented arthroplasties: Present status, key issues, and future prospects

“…The cross-linking agents that have been used in alternative bone cement formulations are ethylene glycol dimethacrylate (EGDMA), triethylene glycol dimethacrylate (TEGDMA), poly(ethylene glycol) dimethacrylate (PEGDMA), and poly (MMA-co-AA-co-allylmethacrylate). 78,79 By providing anchoring points for the PMMA matrix in the cement, these agents are expected to cause an insoluble network to form during its polymerization, and, so, an increase in both the stiffness and K IC of the cement and a decrease in its volumetric shrinkage are expected to occur. The form in which these agents were incorporated into the cement influences the changes in properties determined (relative to those of a control cement).…”

Microencapsulation of Liquid Cyanoacrylate via In Situ Polymerization for Self-healing Bone Cement Application – ERRATUM

“…Loosening of cemented implants is usually caused by mechanical failure of the PMMA bone cement under cyclic loading [7]. Previous studies have addressed these problems by modifying the cement formulation through the addition of cross linking agents [8,9], increasing tensile strength and fracture toughness by reinforcing with metallic wires, or incorporating covalently connected SiO 2 glass networks to prevent bone cement failure [10][11][12]. However, limited success was seen in resolving "damage accumulation failure" of the cemented implants.…”