What Type of LLDPE Is Shenhua 7042? A Complete Guide to Classification Logic of Film-Grade Polyethylene
Introduction
Most buyers in film processing only know that 7042 can be used for packaging bags and agricultural mulch films, without a clear idea of its position in the LLDPE product system. Linear low-density polyethylene is classified by multiple industry standards. This article avoids complicated physical property parameters, sorts out categories of film-grade LLDPE with universal industry logic, and clarifies the applicable scenarios of Shenhua 7042. Simply put: Shenhua 7042 is a general blown-film type under film-grade LLDPE, adopting butene copolymerization (C4) system and produced via coal-to-olefin process.
Three Basic Categories of LLDPE by Processing Application
LLDPE is divided into three non-interchangeable categories based on downstream processing technology:
Film-grade LLDPE: Designed for blown and cast film extrusion with stable film forming performance, the dominant raw material for packaging and agricultural film manufacturers.
Injection-grade LLDPE: Features higher fluidity, only for injection molding plastic products and unsuitable for film production.
Rotomolding/coating-grade LLDPE: Developed for thick-wall products and coating processes, rarely applied in film manufacturing.
Most common grades under the 7042 series fall into film-grade LLDPE, mainly applied to blown film production lines.
Four Subcategories of Film-Grade LLDPE
Film-grade LLDPE can be split into four subcategories by formula and performance orientation:
General blown-film grade: Balanced comprehensive performance and controllable cost, ideal for daily shopping bags and standard agricultural mulch films.
Heavy-duty packaging grade: Outstanding puncture and tear resistance, used for industrial heavy-load packaging sacks.
Metallocene LLDPE: Produced with special catalyst technology, it outperforms conventional LLDPE in tensile strength, heat-sealing property and transparency, widely adopted for premium food packaging films.
Anti-aging agricultural film grade: Pre-blended with UV stabilizers during production, dedicated to greenhouse films exposed outdoors long-term.
Apart from application-based classification, LLDPE can also be categorized by comonomer type. Butene (C4) copolymerized LLDPE has the largest output and superior cost performance, while hexene (C6) and octene (C8) copolymerized grades deliver better mechanical properties at a higher purchase cost. All 7042 grades follow the butene copolymerization route.
Exact Category Positioning of Shenhua 7042
Shenhua 7042 is defined from three dimensions. In processing, it is a dedicated blown-film resin compatible with regular blown film equipment, offering high fault tolerance for mass production. In application, it belongs to general blown-film grade without special reinforcement for heavy load, high transparency or anti-aging performance. In raw material route, it is domestic coal-based LLDPE adopting mature butene copolymerization system.
7042 is a universal grade number manufactured by multiple petrochemical enterprises. Shenhua 7042 adopts coal-based raw materials, while Daqing, Dushanzi 7042 are oil-based products. They share similar basic physical properties but differ greatly in supply cycle and price fluctuation. Grades from different manufacturers vary in additive systems; Shenhua 7042 contains no pre-added slip and opening agents, allowing processors to adjust additives independently according to production line demands. Shenhua 7042 film-grade LLDPE boasts balanced overall performance, serving as a mainstream alternative to imported general film resins for small and medium film factories.
Quick Reference for Applicable Scenarios
Suitable for Shenhua 7042: Supermarket shopping bags, garbage bags, standard agricultural mulch films, light-duty inner packaging films for food products.Unsuitable for: Industrial heavy-load sacks, long-term outdoor greenhouse films, premium stretch wrap films, injection-molded plastic parts.
Conclusion
LLDPE is first categorized into film, injection and rotomolding grades by processing technology. Film-grade resins are further divided into four application-based subcategories, and all LLDPE can be grouped into butene, hexene and octene copolymerized types by comonomer. The core positioning of Shenhua 7042 is coal-based butene copolymerized general blown-film LLDPE, targeting cost-effective mass production scenarios. Instead of blindly choosing high-end grades, buyers should select resins matching their product specifications to strike a balance between production cost and finished product quality.
