The raw material ratio of vinyl bear ornaments is a key factor influencing the flexibility and gloss of the finished product. Through the synergistic effect of molecular structure design and additives, it directly determines the physical properties and surface quality of the material after molding. Vinyl monomers, as the basic components, play a dominant role in flexibility, depending on their type and ratio. For example, in ethylene-acrylate copolymers, the introduction of acrylate monomers can significantly improve the material's flexibility. This is because the length of the ester carbon chain is related to molecular chain mobility. Long chains enhance chain segment mobility, making bear ornaments more susceptible to elastic deformation and less prone to breakage under load. Conversely, if the ratio of rigid monomers (such as styrene) is too high, the intermolecular forces increase, leading to increased brittleness and reduced flexibility.
Gloss is closely related to the crystallization behavior of the raw material ratio. The crystallinity of vinyl resin directly affects surface smoothness. Highly crystalline materials exhibit high gloss due to the densely packed molecular chains, which more concentratedly reflect light. Low crystallinity or amorphous structures, on the other hand, scatter light, resulting in lower gloss. In raw material design, adjusting the ratio of ethylene to comonomer can control the distribution of crystalline regions. For example, increasing the ethylene content may reduce overall crystallinity, but this must be balanced against the need for flexibility. Introducing polar monomers (such as acrylic acid) may further affect gloss by disrupting crystal integrity.
The additive ratio has a dual regulatory effect on both flexibility and gloss. Plasticizers, as key additives, enhance flexibility by reducing intermolecular forces, but their type and dosage require precise control. Excessive plasticizer use can cause surface stickiness and affect gloss. Selecting plasticizers with good compatibility with vinyl resins (such as phthalates) can maintain a smooth surface while ensuring flexibility. Furthermore, the addition of lubricants can reduce friction during processing, prevent surface scratches, and indirectly improve gloss. However, careful consideration should be given to their compatibility with the resin to prevent migration and surface blurring.
The choice of filler in the raw material mix significantly influences gloss. While inorganic fillers (such as calcium carbonate and talc) can reduce costs, they can scatter light and reduce gloss due to the difference in refractive index with the resin matrix. Spherical fillers, due to their small surface area and reduced light interference, are more conducive to maintaining high gloss than flake or needle-shaped fillers. Smaller filler particle size results in more uniform dispersion, fewer surface defects, and higher gloss. Therefore, when designing raw materials for vinyl bear ornaments, a balance must be struck between filler type and dosage to avoid overfilling that compromises surface quality.
The polarity of comonomers has varying effects on flexibility and gloss. The introduction of polar monomers (such as methacrylic acid) enhances interchain forces and improves material strength, but may reduce flexibility. Non-polar monomers (such as ethylene) are more conducive to maintaining chain segment freedom of movement. Regarding gloss, polar monomers may enhance crystallization, but the crystal morphology must be optimized in conjunction with processing techniques (such as injection molding temperature) to avoid surface roughness caused by uneven crystallization.
Optimizing raw material ratios also requires consideration of synergistic effects within the processing technology. For example, vinyl resins with a high melt flow index (MFI) fill the mold more easily during injection molding, reducing surface flow marks and improving gloss. Low-flow-index materials, on the other hand, may cause surface defects due to insufficient filling. Therefore, raw material design must be matched with processing parameters (such as mold temperature and injection speed) to ensure sufficient material flow and rapid crystallization during the molding process, resulting in a smooth surface.
The raw material ratio for vinyl bear ornaments is influenced by the synergistic effects of monomer type, additive selection, filler properties, and processing technology, which collectively influence the final product's flexibility and gloss. Precisely controlling the ratio of vinyl monomer to comonomer, judiciously selecting additives and fillers, and matching processing parameters are key to achieving a balance between material performance and surface quality. This process requires a combination of experimental verification and theoretical analysis to continuously optimize the formulation to meet the market's dual demands for aesthetics and durability.
