{"id":16675,"date":"2025-10-24T09:14:52","date_gmt":"2025-10-24T06:14:52","guid":{"rendered":"https:\/\/novateplica.com.ua\/?p=16675"},"modified":"2025-10-24T09:14:52","modified_gmt":"2025-10-24T06:14:52","slug":"pochemu-poyavlyayutsya-mikrotreshhiny-v-polikarbonate-prakticheskij-razbor-ot-novateplicza","status":"publish","type":"post","link":"https:\/\/novateplica.com.ua\/en\/pochemu-poyavlyayutsya-mikrotreshhiny-v-polikarbonate-prakticheskij-razbor-ot-novateplicza\/","title":{"rendered":"Why microcracks appear in polycarbonate: A practical analysis from NovaTeplitsa"},"content":{"rendered":"

Polycarbonate has earned the trust of farmers and private farm owners as the ideal material for greenhouses. Its advantages are obvious: high transparency, exceptional strength (200 times stronger than glass), lightweight, and excellent thermal insulation properties. However, over time, some owners notice a fine network of cracks, known as "spiderweb," on the material's surface.<\/p>\n

In this article, NovaTeplitsa experts, drawing on their many years of experience working with polycarbonate, will examine in detail why microcracks occur, how they affect a greenhouse, and, most importantly, how to avoid them.<\/p>\n

What are microcracks and why are they dangerous?<\/h2>\n

Microcracks are small surface damages on a polycarbonate sheet. They are initially barely noticeable, but can deepen over time.<\/p>\n

The danger lies not only in the aesthetic defect. Due to microcracks:<\/p>\n

    \n
  1. Light transmittance decreases:<\/strong> The material becomes cloudy, and the plants in the greenhouse do not receive critical sunlight.<\/li>\n
  2. Thermal insulation deteriorates:<\/strong> In cellular polycarbonate, cracks can lead to depressurization of the cells, allowing moisture and dirt to enter them.<\/li>\n
  3. Strength decreases:<\/strong> The leaf becomes brittle and more vulnerable to mechanical stress such as hail or strong wind.<\/li>\n<\/ol>\n

    Understanding the reasons is the first step to durable and efficient greenhouse<\/a>.<\/p>\n

    Reason #1: Lack of or poor quality UV protection<\/h2>\n

    \"microcracks<\/p>\n

    This is the most common and serious cause. Polycarbonate, by its chemical nature, is vulnerable to ultraviolet radiation. Without proper protection, sunlight destroys the polymer chains, making the material brittle and yellow.<\/p>\n

    How does this work:<\/strong> Qualitative polycarbonate for greenhouses<\/a> It has a coextruded UV protective layer. This isn't just a simple coating, but a 30-60 micron thick layer "fused" into the sheet surface during production.<\/p>\n

    Risk factor:<\/strong> There's a lot of cheap, no-name polycarbonate on the market, or so-called "lightweight" (eco) sheets. These sheets either lack a protective layer, or have a minimal thickness (10-15 microns), or are applied unevenly. This material begins to deteriorate within 2-3 years of use.<\/p>\n

    Comparison table: High-quality and inexpensive polycarbonate<\/h3>\n\n\n\n\n\n\n\n
    Feature \/ Parameter<\/th>\nHigh-quality certified polycarbonate<\/th>\nCheap "eco" or "no-name" polycarbonate<\/th>\n<\/tr>\n
    UV protective layer<\/strong><\/td>\nCoextrusion, 30-60 microns<\/td>\nNone or < 20 microns, spray applied<\/td>\n<\/tr>\n
    Raw materials<\/strong><\/td>\n100% virgin polycarbonate<\/td>\nAddition of secondary raw materials (recycled PC)<\/td>\n<\/tr>\n
    Manufacturer's warranty<\/strong><\/td>\n10-15 years (real, documentary)<\/td>\nAbsent, or 1-3 years (conditional)<\/td>\n<\/tr>\n
    Result in 3-5 years<\/strong><\/td>\nMaintains transparency and strength<\/td>\nIt turns yellow, becomes brittle, and becomes covered with microcracks.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

    Expert advice:<\/strong> NovaTeplitsa always recommends requesting certificates of conformity from the seller and checking the markings on the sheet's protective film. These clearly indicate which side of the sheet contains the UV layer (this side should be on the outside of the greenhouse) and the manufacturer's warranty period.<\/p><\/blockquote>\n

    Reason #2: Installation errors and \u201cinternal stress\u201d<\/h2>\n

    \"microcracks<\/p>\n

    Even the most expensive premium polycarbonate can be ruined by improper installation. The main enemy is neglect. thermal expansion<\/strong> material. This is not just a recommendation, but a law of physics.<\/p>\n

    Technical data:<\/strong> Polycarbonate has a significant coefficient of linear thermal expansion\u2014approximately 0.065 mm\/m\u00b0C. This means that a 6-meter sheet can expand by 1.95 cm in length when exposed to a temperature difference of 50\u00b0C (for example, from -10\u00b0C in winter to +40\u00b0C in the sun in summer).<\/p>\n

    Errors that lead to cracks:<\/strong><\/p>\n

      \n
    1. Rigid mount:<\/strong> The sheets are screwed directly to the frame. When the polycarbonate expands, it pushes against the fasteners, creating enormous internal stress. It is at these points that cracking begins.<\/li>\n
    2. Incorrect holes:<\/strong> The holes for the screws are drilled \u201cbutt-to-toe\u201d (less than 2-3 mm of reserve).<\/li>\n
    3. Using regular screws:<\/strong> Lack of sealing and cushioning.<\/li>\n<\/ol>\n

      The right solution (Installation technology):<\/strong><\/p>\n